U.S. patent application number 13/016847 was filed with the patent office on 2011-08-04 for polymer compound and light emitting device using the same.
This patent application is currently assigned to SUMITOMO CHEMICAL COMPANY, LIMITED. Invention is credited to Natasha CONWAY, Daisuke FUKUSHIMA, Mary MCKIERNAN, Kazuei OHUCHI, Brian TIERNEY.
Application Number | 20110187266 13/016847 |
Document ID | / |
Family ID | 43824793 |
Filed Date | 2011-08-04 |
United States Patent
Application |
20110187266 |
Kind Code |
A1 |
FUKUSHIMA; Daisuke ; et
al. |
August 4, 2011 |
POLYMER COMPOUND AND LIGHT EMITTING DEVICE USING THE SAME
Abstract
A polymer compound that, when used for fabrication of a light
emitting device, results in an excellent luminance lifetime for the
obtained light emitting device. A polymer compound comprising a
constitutional unit represented by formula (1). ##STR00001## (In
the formula, R.sup.1 and R.sup.2 each independently represent an
unsubstituted alkyl group. R.sup.3 and R.sup.4 each independently
represent a group other than an unsubstituted alkyl group. R.sup.5
and R.sup.6 each independently represent an unsubstituted or
substituted alkyl, unsubstituted or substituted alkoxy or
unsubstituted or substituted aryl group. The letters a and b each
independently represent an integer of 0-4. The letters c and d each
independently represent an integer of 0-3. When multiple R.sup.3,
R.sup.4, R.sup.5 and R.sup.6 groups are present, they may be the
same or different.)
Inventors: |
FUKUSHIMA; Daisuke;
(Ushiku-shi, JP) ; OHUCHI; Kazuei; (Tsukuba-shi,
JP) ; TIERNEY; Brian; (Cambridgeshire, GB) ;
CONWAY; Natasha; (Cambridgeshire, GB) ; MCKIERNAN;
Mary; (Cambridgeshire, GB) |
Assignee: |
SUMITOMO CHEMICAL COMPANY,
LIMITED
Tokyo
JP
CAMBRIDGE DISPLAY TECHNOLOGY LIMITED
Cambridgeshire
GB
|
Family ID: |
43824793 |
Appl. No.: |
13/016847 |
Filed: |
January 28, 2011 |
Current U.S.
Class: |
313/504 ;
252/301.35; 528/8 |
Current CPC
Class: |
C08G 2261/3162 20130101;
C09K 2211/1425 20130101; C08G 2261/512 20130101; C09K 2211/1433
20130101; H01L 51/0039 20130101; H01L 51/0043 20130101; C08G 61/02
20130101; C09K 2211/1466 20130101; C09K 2211/1416 20130101; C08G
61/122 20130101; C09K 2211/1483 20130101; C09K 2211/1458 20130101;
C08G 2261/3245 20130101; C09K 11/06 20130101; C08G 2261/411
20130101; H01L 51/5012 20130101; C08G 61/12 20130101; C08G
2261/3142 20130101; C08G 2261/5222 20130101; C08G 2261/95
20130101 |
Class at
Publication: |
313/504 ; 528/8;
252/301.35 |
International
Class: |
H01J 1/63 20060101
H01J001/63; C08G 79/08 20060101 C08G079/08; C09K 11/02 20060101
C09K011/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 28, 2010 |
JP |
P2010-016532 |
Claims
1. A polymer compound comprising a constitutional unit represented
by formula (1): ##STR00115## (wherein in the formula (1), R.sup.1
and R.sup.2 each independently represent an unsubstituted alkyl
group, R.sup.3 and R.sup.4 each independently represent a group
other than an unsubstituted alkyl group, R.sup.5 and R.sup.6 each
independently represent an unsubstituted or substituted alkyl,
unsubstituted or substituted alkoxy or unsubstituted or substituted
aryl group, the letters a and b each independently represent an
integer of 0-4, the letters c and d each independently represent an
integer of 0-3, and when multiple R.sup.3, R.sup.4, R.sup.5 and
R.sup.6 groups are present, they may be the same or different.
2. The polymer compound according to claim 1, wherein the
constitutional unit represented by formula (1) is a constitutional
unit represented by formula (2): ##STR00116## (wherein in the
formula, R.sup.7 and R.sup.8 each independently represent an
unsubstituted alkyl group.
3. The polymer compound according to claim 2, wherein the
constitutional unit represented by formula (2) is a constitutional
unit represented by formula (3), (4), (5), (3A), (4A) or (5A):
##STR00117## (wherein in formula (3), (4), (5), (3A), (4A) and
(5A), R.sup.7 and R.sup.8 have the same meaning as above.
4. The polymer compound according to claim 1, wherein the
constitutional unit represented by formula (1) is a constitutional
unit represented by formula (2A): ##STR00118## (wherein in the
formula, R.sup.3 and R.sup.4 have the same meaning as above,
R.sup.7 and R.sup.8 each independently represent an unsubstituted
alkyl group, the letters a1 and b1 each independently represent an
integer of 1-4, and when multiple R.sup.3 and R.sup.4 groups are
present, they may be the same or different.
5. The polymer compound according to claim 1, which further
comprises one or more constitutional units selected from the group
consisting of constitutional units represented by formula (6) and
constitutional units represented by formula (7): ##STR00119##
(wherein in the formula (6), Ar.sup.1 represents an unsubstituted
or substituted arylene or unsubstituted or substituted divalent
heterocyclic group, in the formula (7), Ar.sup.2, Ar.sup.3 and
Ar.sup.4 each independently represent an unsubstituted or
substituted arylene group, an unsubstituted or substituted divalent
aromatic heterocyclic group, or an unsubstituted or substituted
divalent group bonded to two aromatic rings by a single bond,
R.sup.A and R.sup.B each independently represent hydrogen, an
unsubstituted or substituted alkyl group, an unsubstituted or
substituted aryl group, or an unsubstituted or substituted
monovalent heterocyclic group, and the letter e represents 0 or
1.
6. The polymer compound according to claim 5, wherein the
constitutional unit represented by formula (6) is a constitutional
unit represented by formula (8), (9) or (10): ##STR00120## (wherein
in the formula (8), R.sup.9 represents an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonylaryl group,
the letter f represents an integer of 0-4, multiple R.sup.9 groups
may be the same or different, wherein in the formula (9), R.sup.10
and R.sup.11 each independently represent an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkoxyaryl
or unsubstituted alkoxycarbonylaryl group, and wherein in the
formula (10), R.sup.12 represents an unsubstituted alkyl,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl or unsubstituted alkoxycarbonylaryl group, X is a single
bond, --O--, --S-- or --C(R.sup.C) R.sup.C represents an
unsubstituted alkyl, unsubstituted aryl, unsubstituted alkylaryl or
unsubstituted alkoxyaryl group, and the two R.sup.C groups may be
the same or different.
7. The polymer compound according to claim 5, wherein the
constitutional unit represented by formula (7) is a constitutional
unit represented by formula (14): ##STR00121## (wherein in the
formula (14), Ar.sup.4 has the same meaning as above, R.sup.D and
R.sup.E each independently represent an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonyl group, the
letters h and i each independently represent an integer of 0-5.
When multiple R.sup.D and R.sup.E groups are present, they may be
the same or different, and the letter e represents 0 or 1.
8. The polymer compound according to claim 1, which further
comprises one or more constitutional units selected from the group
consisting of constitutional units represented by formula (11),
constitutional units represented by formula (12) and constitutional
units represented by formula (13): ##STR00122## (wherein in the
formula (11), R.sup.13 and R.sup.13' each independently represent
hydrogen or an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl or unsubstituted alkoxycarbonylaryl group, wherein in
the formula (12), R.sup.14, R.sup.15, R.sup.16, R.sup.17, R.sup.18
and R.sup.19 each independently represent hydrogen or an
unsubstituted alkyl, unsubstituted alkoxy, unsubstituted aryl,
unsubstituted alkylaryl, unsubstituted alkoxyaryl or unsubstituted
alkoxycarbonylaryl group, wherein in the formula (13), R.sup.20
represents an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted aryl, alkylaryl, unsubstituted alkoxyaryl or
unsubstituted alkoxycarbonylaryl group, the letter g represents an
integer of 0-5. Multiple R.sup.20 groups may be the same or
different.
9. The polymer compound according to claim 7, which consists of: a
constitutional unit represented by formula (1), and one or more
constitutional units selected from the group consisting of
constitutional units represented by formula (8), constitutional
units represented by formula (9), constitutional units represented
by formula (10) and constitutional units represented by formula
(14).
10. The polymer compound according to claim 8, which consists of: a
constitutional unit represented by formula (1), at least one
constitutional unit selected from the group consisting of
constitutional units represented by formula (8), constitutional
units represented by formula (9), constitutional units represented
by formula (10) and constitutional units represented by formula
(14), and at least one constitutional unit selected from the group
consisting of constitutional units represented by formula (11),
constitutional units represented by formula (12) and constitutional
units represented by formula (13).
11. A composition comprising at least one material selected from
the group consisting of hole transport materials, electron
transport materials and luminescent materials, and a polymer
compound according to claim 1.
12. A composition according to claim 11, wherein the luminescent
materials is a triplet light emitting complex.
13. A composition comprising a polymer compound according to claim
1, and a solvent.
14. A thin-film comprising a polymer compound according to claim
1.
15. A light emitting device having electrodes consisting of an
anode and a cathode, and a layer comprising a polymer compound
according to claim 1 formed between the electrodes.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a polymer compound. More
specifically, the present invention relates to a fluorene-based
polymer compound and to a light emitting device using it.
[0003] 2. Related Background Art
[0004] Light emitting devices such as organic electroluminescence
devices have been an object of interest in recent years as their
properties including low voltage driving and high luminance render
them suitable for use in displays and the like. Luminescent
materials and charge transport materials are used in the production
of light emitting devices.
[0005] Polymer compounds that allow formation of organic layers by
dissolution in solvents and coating are being studied as
luminescent materials and charge transport materials, and as such
polymer compounds there have been proposed polymer compounds that
comprise constitutional units derived from fluorene having alkyl
group substituents (Patent literature 1).
CITATION LIST
Patent Literature
[0006] [Patent literature 1] Japanese Patent Public Inspection No.
2001-520289
SUMMARY OF THE INVENTION
[0007] However, when the polymer compounds mentioned above are used
to fabricate light emitting devices, the luminance lifetime of the
light emitting devices are less than adequate.
[0008] It is therefore an object of the present invention to
provide a polymer compound that, when used for fabrication of a
light emitting device, results in an excellent luminance lifetime
for the obtained light emitting device.
[0009] To achieve the objective mentioned above, the invention
provides, firstly, a polymer compound comprising a constitutional
unit represented by formula (1).
##STR00002##
(In formula (1), R.sup.1 and R.sup.2 each independently represent
an unsubstituted alkyl group. R.sup.3 and R.sup.4 each
independently represent a group other than an unsubstituted alkyl
group. R.sup.5 and R.sup.6 each independently represent an
unsubstituted or substituted alkyl, unsubstituted or substituted
alkoxy or unsubstituted or substituted aryl group. The letters a
and b each independently represent an integer of 0-4. The letters c
and d each independently represent an integer of 0-3. When multiple
R.sup.3, R.sup.4, R.sup.5 and R.sup.6 groups are present, they may
be the same or different.)
[0010] The constitutional unit represented by formula (1) is
preferably a constitutional unit represented by formula (2).
##STR00003##
(In formula (2), R.sup.7 and R.sup.8 each independently represent
an unsubstituted alkyl group.)
[0011] The constitutional unit represented by formula (2) is
preferably a constitutional unit represented by formula (3), (4),
(5), (3A), (4A) or (5A).
##STR00004##
(In formula (3), (4), (5), (3A), (4A) and (5A), R.sup.7 and R.sup.8
have the same meaning as above.)
[0012] The constitutional unit represented by formula (1) may also
preferably be a constitutional unit represented by formula
(2A).
##STR00005##
(In formula (2A), R.sup.3 and R.sup.4 have the same meaning as
above. R.sup.7 and R.sup.8 each independently represent an
unsubstituted alkyl group. The letters a1 and b1 each independently
represent an integer of 1-4. When multiple R.sup.3 and R.sup.4
groups are present, they may be the same or different.)
[0013] The polymer compound of the invention preferably further
comprises one or more constitutional units selected from the group
consisting of constitutional units represented by formula (6) and
constitutional units represented by formula (7).
##STR00006##
(In formula (6), Ar.sup.1 represents an unsubstituted or
substituted arylene or unsubstituted or substituted divalent
heterocyclic group. In formula (7), Ar.sup.2, Ar.sup.3 and Ar.sup.4
each independently represent an unsubstituted or substituted
arylene group, an unsubstituted or substituted divalent aromatic
heterocyclic group, or an unsubstituted or substituted divalent
group bonded to two aromatic rings by a single bond. R.sup.A and
R.sup.B each independently represent hydrogen, an unsubstituted or
substituted alkyl group, an unsubstituted or substituted aryl
group, or an unsubstituted or substituted monovalent heterocyclic
group. The letter e represents 0 or 1.)
[0014] In particular, the constitutional unit represented by
formula (6) is preferably a constitutional unit represented by
formula (8), (9) or (10).
##STR00007##
(In formula (8), R.sup.9 represents an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonylaryl group.
The letter f represents an integer of 0-4. Multiple R.sup.9 groups
may be the same or different.
[0015] In formula (9), R.sup.10 and R.sup.11 each independently
represent an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkoxyaryl or unsubstituted
alkoxycarbonylaryl group. In formula (10), R.sup.12 represents an
unsubstituted alkyl, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonylaryl group.
X is a single bond, --O--, --S-- or --C(R.sub.C).sub.2--. R.sup.C
represents an unsubstituted alkyl, unsubstituted aryl,
unsubstituted alkylaryl or unsubstituted alkoxyaryl group, and the
two R.sup.C groups may be the same or different.
[0016] The constitutional unit represented by formula (7) is
preferably a constitutional unit represented by formula (14).
##STR00008##
(In formula (7), Ar.sup.4 has the same meaning as above. R.sup.D
and R.sup.E each independently represent an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonyl group. The
letters h and i each independently represent an integer of 0-5.
When multiple R.sup.D and R.sup.E groups are present, they may be
the same or different. The letter e represents 0 or 1.)
[0017] The polymer compound of the invention more preferably
further comprises one or more constitutional units selected from
the group consisting of constitutional units represented by formula
(11), constitutional units represented by formula (12) and
constitutional units represented by formula (13).
##STR00009##
(In formula (11), R.sup.13 and R.sup.13' each independently
represent hydrogen or an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl or unsubstituted alkoxycarbonylaryl group. In formula
(12), R.sup.14, R.sup.15, R.sup.16, R.sup.17, R.sup.18 and R.sup.19
each independently represent hydrogen or an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonylaryl group.
In formula (13), R.sup.20 represents an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, alkylaryl, unsubstituted
alkoxyaryl or unsubstituted alkoxycarbonylaryl group. The letter g
represents an integer of 0-5. Multiple R.sup.20 groups may be the
same or different.
[0018] From the above viewpoint, the polymer compound of the
invention preferably consists of a constitutional unit represented
by formula (1), and one or more constitutional units selected from
the group consisting of constitutional units represented by formula
(8), constitutional units represented by formula (9),
constitutional units represented by formula (10) and constitutional
units represented by formula (14).
[0019] The polymer compound of the invention may also preferably
consist of a constitutional unit represented by formula (1),
at least one constitutional unit selected from the group consisting
of constitutional units represented by formula (8), constitutional
units represented by formula (9), constitutional units represented
by formula (10) and constitutional units represented by formula
(14), and at least one constitutional unit selected from the group
consisting of constitutional units represented by formula (11),
constitutional units represented by formula (12) and constitutional
units represented by formula (13).
[0020] The invention provides, secondly, a composition comprising
at least one material selected from the group consisting of hole
transport materials, electron transport materials and luminescent
materials, and the aforementioned polymer compound of the
invention, as well as a composition comprising the aforementioned
polymer compound of the invention and a solvent. The luminescent
material is preferably a triplet light emitting complex.
[0021] The invention provides, thirdly, a thin-film comprising the
polymer compound of the invention.
[0022] The invention provides, fourthly, a light emitting device
having electrodes consisting of an anode and a cathode, and a layer
comprising the aforementioned polymer compound formed between the
electrodes thereof.
[0023] By having the specific structures mentioned above, the
polymer compound of the invention is a polymer compound that, when
used to fabricate a light emitting device, results in an excellent
luminance lifetime of the obtained light emitting device.
Therefore, the polymer compound of the invention is useful, for
example, as an electronic part material, such as a luminescent
material or charge transport material. Thus, the polymer compound
and light emitting device of the invention are useful for liquid
crystal display backlights, curved or flat light sources for
illumination, segment type display devices, dot matrix flat panel
displays, and the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a schematic cross-sectional view of an embodiment
of the light emitting device of the invention.
[0025] FIG. 2 is a schematic cross-sectional view of other
embodiment of the light emitting device of the invention.
[0026] FIG. 3 is a schematic cross-sectional view of an embodiment
of the planar light source of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0027] The terms used throughout the present specification will be
explained first.
[0028] The term "constitutional unit" refers to a unit of which at
least one is present in the polymer compound.
The term "n-valent heterocyclic group" (n being 1 or 2) refers to a
group derived by removing n hydrogen atoms from a heterocyclic
compound (especially an aromatic heterocyclic compound). The term
"heterocyclic compound" refers to an organic compound with a ring
structure, wherein the devices composing the ring are not only
carbon atoms but include a heteroatom such as an oxygen atom,
sulfur atom, nitrogen atom, phosphorus atom or boron atom. The term
"arylene group" refers to an atomic group derived by removing 2
hydrogens from an aromatic hydrocarbon. The term "aryl group"
refers to an atomic group derived by removing one hydrogen from an
aromatic hydrocarbon, and it includes groups with fused rings, and
directly bonded independent benzene rings or two or more fused
rings.
[0029] <Polymer Compound>
The following is a detailed description of the polymer compound of
the preferable embodiment.
[0030] --Constitutional Unit Represented by Formula (1)--
The polymer compound of the invention comprises a constitutional
unit represented by formula (1) above.
[0031] In formula (1), R.sup.1 and R.sup.2 each independently
represent an unsubstituted alkyl group. The unsubstituted alkyl
group may be a straight-chain, branched or cyclic group. Usually
the unsubstituted alkyl group will have 1-20, preferably 1-15, more
preferably 3-10 and even more preferably 4-8 carbon atoms.
Unsubstituted alkyl groups include methyl, ethyl, n-propyl,
isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isoamyl,
n-hexyl, cyclohexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl,
n-decyl, 3,7-dimethyloctyl and lauryl. Since balance between
solubility of the polymer compound in organic solvents and heat
resistance is improved, they are preferably methyl, ethyl,
n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl,
isoamyl, n-hexyl, n-octyl, 2-ethylhexyl or 3,7-dimethyloctyl
groups, and more preferably n-butyl, isobutyl, tert-butyl,
n-pentyl, isoamyl, n-hexyl, n-octyl, 2-ethylhexyl or
3,7-dimethyloctyl groups.
[0032] In formula (1), R.sup.3 and R.sup.4 each independently
represent a group other than an unsubstituted alkyl group. Groups
other than unsubstituted alkyl groups are preferably unsubstituted
or substituted alkoxy, unsubstituted or substituted aryl,
unsubstituted or substituted aryloxy, unsubstituted or substituted
monovalent heterocyclic, unsubstituted or substituted amino,
unsubstituted or substituted silyl, halogen atoms, unsubstituted
alkoxycarbonyl, unsubstituted carboxyl or cyano groups. More
preferably they are substituted alkyl, unsubstituted or substituted
alkoxy, unsubstituted or substituted aryl, unsubstituted or
substituted monovalent heterocyclic or unsubstituted alkoxycarbonyl
groups, even more preferably unsubstituted or substituted alkoxy,
unsubstituted or substituted aryl or unsubstituted alkoxycarbonyl
groups, and most preferably substituted aryl groups.
[0033] The unsubstituted or substituted alkoxy group may be
straight-chain, branched or cyclic. The number of carbon atoms is
usually 1-20, preferably 1-15, and more preferably 4-10, not
including the number of carbon atoms of substituents. Unsubstituted
or substituted alkoxy groups include methoxy, ethoxy, n-propyloxy,
isopropyloxy, n-butyloxy, isobutyloxy, tert-butyloxy, n-pentyloxy,
n-hexyloxy, cyclohexyloxy, n-heptyloxy, n-octyloxy,
2-ethylhexyloxy, n-nonyloxy, n-decyloxy, 3,7-dimethyloctyloxy,
lauryloxy, trifluoromethoxy, pentafluoroethoxy, perfluorobutoxy,
perfluorohexyloxy, perfluorooctyloxy, methoxymethyloxy,
2-methoxyethyloxy and 2-ethoxyethyloxy groups. Since balance
between solubility of the polymer compound in the organic solvent
and heat resistance is improved, n-butyloxy, n-pentyloxy,
n-hexyloxy, n-octyloxy, 2-ethylhexyloxy, n-decyloxy,
3,7-dimethyloctyloxy and 2-ethoxyethyloxy groups are preferred.
[0034] The number of carbon atoms in the unsubstituted or
substituted aryl group is usually 6-60, preferably 6-48, more
preferably 6-20 and even more preferably 6-10, not including the
number of carbon atoms of substituents. Unsubstituted or
substituted aryl groups include phenyl, 1-naphthyl, 2-naphthyl,
1-anthracenyl, 2-anthracenyl, 9-anthracenyl, 1-pyrenyl, 2-pyrenyl,
4-pyrenyl, 2-perylenyl, 3-perylenyl, 2-fluorenyl, 3-fluorenyl,
4-fluorenyl, 1-biphenylenyl, 2-biphenylenyl, 2-phenanthrenyl,
9-phenanthrenyl, 2-phenylphenyl, 3-phenylphenyl, 4-phenylphenyl,
and these groups whose hydrogen(s) is replaced with alkyl, alkoxy,
alkyloxycarbonyl, acyl, N,N-dialkylamino, N,N-diarylamino, cyano,
nitro, chlorine, fluorine or the like. Since the balance between
solubility of the polymer compound in the organic solvent and heat
resistance is improved, phenyl groups and alkyl-substituted phenyl
groups are preferred.
[0035] Alkyl-substituted phenyl groups include 2-methylphenyl,
3-methylphenyl, 4-methylphenyl, 3-n-butylphenyl, 4-n-butylphenyl,
4-tert-butylphenyl, 3-n-hexylphenyl, 4-n-hexylphenyl,
4-n-octylphenyl, 3,5-dimethylphenyl, 3-n-hexyl-5-methylphenyl and
3,5-dihexylphenyl.
[0036] The number of carbon atoms in the unsubstituted or
substituted aryloxy group is usually 6-60 and preferably 7-48, not
including the number of carbon atoms of substituents. Unsubstituted
or substituted aryloxy groups include phenoxy, 1-naphthyloxy,
2-naphthyloxy, 1-anthracenyloxy, 9-anthracenyloxy, 1-pyrenyloxy,
and these groups whose hydrogen(s) is replaced with alkyl, alkoxy,
alkyloxycarbonyl, acyl, N,N-dialkylamino, N,N-diarylamino, cyano,
nitro, chlorine or fluorine or the like.
[0037] The number of carbon atoms in the unsubstituted or
substituted monovalent heterocyclic group is usually 4-60 and
preferably 4-20, not including the number of carbon atoms of
substituents. Unsubstituted or substituted monovalent heterocyclic
groups include thienyl, pyrrolyl, furyl, pyridyl, piperidyl,
quinolyl, isoquinolyl, pyrimidyl, triazinyl, and these groups whose
hydrogen(s) is replaced with alkyl, alkoxy or the like. Of these,
thienyl, pyridyl, quinolyl, isoquinolyl, pyrimidyl, triazinyl and
these groups whose hydrogen(s) is replaced with alkyl, alkoxy or
the like are preferred, and more preferred are pyridyl, pyrimidyl,
triazinyl and these groups whose hydrogen(s) is replaced with
alkyl, alkoxy or the like.
[0038] The substituted amino groups may be amino groups substituted
with one or more groups selected from the group consisting of
unsubstituted alkyl, unsubstituted or substituted aryl and
unsubstituted or substituted monovalent heterocyclic groups. The
definitions and examples of unsubstituted alkyl, unsubstituted or
substituted aryl and unsubstituted or substituted monovalent
heterocyclic groups are the same as above. The number of carbon
atoms of the substituted amino group will usually be 1-50, is
preferably 2-30, and more preferably 12-24. Substituted amino
groups include methylamino, dimethylamino, di-n-propylamino,
diisopropylamino, di-n-butylamino, di-tert-butylamino,
dicyclohexylamino, di-n-octylamino, phenylamino, diphenylamino,
di(4-methylphenyl)amino and di(4-tert-butylphenyl)amino.
[0039] The substituted silyl groups may be silyl groups substituted
with 1-3 groups selected from the group consisting of unsubstituted
alkyl, unsubstituted or substituted aryl and unsubstituted or
substituted monovalent heterocyclic groups. The definitions and
examples of unsubstituted alkyl, unsubstituted or substituted aryl
and unsubstituted or substituted monovalent heterocyclic groups are
the same as above. The number of carbon atoms in the substituted
silyl group is usually 1-60 and preferably 3-48. Substituted silyl
groups include trimethylsilyl, triethylsilyl, tri-n-propylsilyl,
tri-isopropylsilyl, dimethyl-isopropylsilyl,
tert-butyldimethylsilyl, triphenylsilyl, tri-p-xylylsilyl,
tribenzylsilyl, diphenylmethylsilyl, tert-butyldiphenylsilyl and
dimethylphenylsilyl.
[0040] Halogen atoms include fluorine, chlorine, bromine and iodine
atoms, with fluorine atoms being preferred.
[0041] The number of carbon atoms of the unsubstituted
alkoxycarbonyl group is usually 2-60 and preferably 2-10.
Unsubstituted alkoxycarbonyl groups include methoxycarbonyl,
ethoxycarbonyl, n-propyloxycarbonyl, isopropyloxycarbonyl,
n-butyloxycarbonyl and tert-butyloxycarbonyl.
[0042] In formula (1), R.sup.5 and R.sup.6 each independently
represent an unsubstituted or substituted alkyl, unsubstituted or
substituted alkoxy or unsubstituted or substituted aryl group.
[0043] The definitions and examples of unsubstituted alkyl groups
represented by R.sup.5 and R.sup.6 are the same as the definitions
and examples of unsubstituted alkyl groups represented by R.sup.1
and R.sup.2.
[0044] The substituted alkyl groups represented by R.sup.5 and
R.sup.6 may be straight-chain, branched or cyclic. The number of
carbon atoms is usually 1-20, preferably 1-15 and more preferably
1-10, not including the number of carbon atoms of substituents. The
substituted alkyl groups may include alkyl groups substituted with
halogen atoms, such as trifluoromethyl, pentafluoroethyl,
perfluorobutyl, perfluorohexyl and perfluorooctyl, alkyl groups
substituted with aryl groups, such as phenylmethyl and
4-(4-hexylphenyl)butyl, and alkyl groups substituted with alkoxy
groups such as ethyloxymethyl and ethyloxyethyl.
[0045] The definitions and examples of unsubstituted or substituted
alkoxy groups and unsubstituted and substituted aryl groups
represented by R.sup.5 and R.sup.6 are, respectively, the same
definitions and examples of unsubstituted or substituted alkoxy
groups and unsubstituted and substituted aryl groups represented by
R.sup.3 and R.sup.4.
[0046] In formula (1), a and b each independently represent an
integer of 0-4, preferably represent an integer of 0-2, more
preferably represent 0 or 1, and even more preferably represent
0.
[0047] In formula (1), c and d each independently represent an
integer of 0-3, preferably represent an integer of 0 or 1, and even
more preferably represent 0.
[0048] Since luminance lifetime is better when the polymer compound
is used for fabrication of a light emitting device, the
constitutional unit represented by formula (1) is preferably a
constitutional unit represented by formula (2), more preferably a
constitutional unit represented by formula (3), (4), (5), (3A),
(4A) or (5A), more preferably a constitutional unit represented by
formula (3), (4), (3A), (4A) or (5A) above, particularly preferably
a constitutional unit represented by formula (4), (4A) or (5A)
above, and most preferably a constitutional unit represented by
formula (4) above.
##STR00010## ##STR00011##
(In formulas (2), (3), (4), (5), (3A), (4A) and (5A), respectively,
R.sup.7 and R.sup.8 represent unsubstituted alkyl groups.)
[0049] The definitions and examples of unsubstituted alkyl groups
represented by R.sup.7 and R.sup.8 in formulas (2), (3), (4), (5),
(3A), (4A) and (5A) are the same as the definitions and examples of
unsubstituted alkyl groups represented by R.sup.1 and R.sup.2 in
formula (1).
[0050] Also, since the heat resistance of the polymer compound and
driving voltage of the obtained light emitting device are better,
the constitutional unit represented by formula (1) may preferably
be a constitutional unit represented by formula (2A):
##STR00012##
(In (2A), R.sup.3, R.sup.4, R.sup.7 and R.sup.8 have the same
meaning as above. a1 and b1 each independently represent an integer
of 1-4. When multiple R.sup.3 and R.sup.4 groups, respectively, are
present each of them may be the same or different).
[0051] The symbols a1 and b1 in formula (2A) each independently
represent an integer of 1-4, preferably represent 1 or 2, more
preferably represent 1. Further more preferably both a1 and b1
represent 1.
[0052] From the viewpoint of the luminance lifetime of the obtained
light emitting device, the constitutional unit represented by
formula (1) is preferably a constitutional unit represented by any
of formulas (1A-1)-(1A-6), formulas (1B-1)-(1B-19), formulas
(1C-1)-(1C-8), formulas (1D-1)-(1D-6), formulas (1E-1)-(1E-4),
formulas (1F-1)-(1F-5), formulas (1G-1)-(1G-12) or formulas
(1H-1)-(1H-9), more preferably a constitutional unit represented by
any of formulas (1A-1)-(1A-6), formulas (1B-1)-(1B-19), formulas
(1C-1)-(1C-8), formulas (1D-1)-(1D-6), formulas (1E-1)-(1E-4),
formulas (1F-1)-(1F-5) or formulas (1G-1)-(1G-12), even more
preferably a constitutional unit represented by any of formulas
(1A-1)-(1A-6), formulas (1B-1)-(1B-19), formulas (1C-1)-(1C-8),
formulas (1D-1)-(1D-6), formulas (1E-1)-(1E-4) or formulas
(1F-1)-(1F-5), particularly preferably a constitutional unit
represented by any of formulas (1A-1)-(1A-6), formulas
(1B-1)-(1B-19), formulas (1D-1)-(1D-6), formulas (1E-1)-(1E-4) or
formulas (1F-1)-(1F-5), most preferably a constitutional unit
represented by any of formulas (1B-1)-(1B-19), formulas
(1E-1)-(1E-4) or formulas (1F-1)-(1F-5), and most especially a
constitutional unit represented by any of formulas
(1B-1)-(1B-19).
##STR00013## ##STR00014## ##STR00015## ##STR00016## ##STR00017##
##STR00018## ##STR00019## ##STR00020## ##STR00021##
[0053] From the viewpoint of heat resistance of the polymer
compound and driving voltage of the obtained light emitting device,
the constitutional unit represented by formula (1) is preferably a
constitutional unit represented by any of formulas (1J-6)-(1J-30).
Of these, more preferably the constitutional unit is represented by
any of formulas (1J-6)-(1J-9), formulas (1J-14)-(1J-17) or formulas
(1J-20)-(1J-25) and, even more preferably, the constitutional unit
is represented by any of formulas (1J-14)-(1J-17) or formulas
(1J-22)-(1J-25). Additionally, especially preferably a
constitutional unit represented by any of formulas (1J-16),
formulas (1J-17) or formulas (1J-22)-(1J-25), and most preferably a
constitutional unit represented by any of formulas (1J-16) or
formulas (1J-17).
##STR00022## ##STR00023## ##STR00024## ##STR00025## ##STR00026##
##STR00027##
[0054] Since the luminance lifetime of the obtained light emitting
device is improved, the polymer compound in the present description
preferably comprises one or more constitutional units selected from
the group consisting of constitutional units represented by formula
(6) and constitutional units represented by formula (7), in
addition to a constitutional unit represented by formula (1).
##STR00028##
(In formula (6), Ar.sup.1 represents an unsubstituted or
substituted arylene or unsubstituted or substituted divalent
heterocyclic group. In formula (7), Ar.sup.2, Ar.sup.3 and Ar.sup.4
each independently represent an unsubstituted or substituted
arylene group, an unsubstituted or substituted divalent aromatic
heterocyclic group, or an unsubstituted or substituted divalent
group linked to a divalent aromatic ring by a single bond. R.sup.A
and R.sup.B each independently represent hydrogen, an unsubstituted
or substituted alkyl group, an unsubstituted or substituted aryl
group, or an unsubstituted or substituted monovalent heterocyclic
group. The letter e represents 0 or 1.)
[0055] In formula (6), Ar.sup.1 represents an unsubstituted or
substituted arylene or unsubstituted or substituted divalent
heterocyclic group. This is with the proviso that the
constitutional unit represented by formula (6) differs from the
constitutional unit represented by formula (1).
[0056] The number of carbon atoms of the unsubstituted or
substituted arylene group represented by Ar.sup.1 is usually 6-60,
preferably 6-30, more preferably 6-18 and even more preferably
6-14, not including the number of carbon atoms of substituents. The
unsubstituted or substituted arylene group may be an unsubstituted
or substituted phenylene group such as 1,4-phenylene, 1,3-phenylene
or 1,2-phenylene, an unsubstituted or substituted naphthalenediyl
group such as 1,4-naphthalenediyl, 1,5-naphthalenediyl or
2,6-naphthalenediyl, an unsubstituted or substituted anthracenediyl
group such as 1,4-anthracenediyl, 1,5-anthracenediyl,
2,6-anthracenediyl or 9,10-anthracenediyl, an unsubstituted or
substituted phenanthrenediyl group such as 2,7-phenanthrenediyl, an
unsubstituted or substituted naphthacenediyl group such as
1,7-naphthacenediyl, 2,8-naphthacenediyl or 5,12-naphthacenediyl,
an unsubstituted or substituted fluorenediyl group such as
2,7-fluorenediyl or 3,6-fluorenediyl, an unsubstituted or
substituted pyrenediyl group such as 1,6-pyrenediyl,
1,8-pyrenediyl, 2,7-pyrenediyl or 4,9-pyrenediyl, or an
unsubstituted or substituted perylenediyl group such as
3,9-perylenediyl or 3,10-perylenediyl, an unsubstituted or
substituted chrysenediyl group such as 2,8-chrysenediyl or
6,12-chrysenediyl, or an unsubstituted or substituted
triphenylenediyl group such as 2,7-triphenylenediyl or
2,11-triphenylenediyl. An unsubstituted or substituted phenylene,
unsubstituted or substituted naphthalenediyl, unsubstituted or
substituted fluorenediyl or unsubstituted or substituted pyrenediyl
group is preferable, and an unsubstituted or substituted phenylene
or unsubstituted or substituted fluorenediyl group is more
preferable.
[0057] The number of carbon atoms of the unsubstituted or
substituted divalent aromatic heterocyclic group represented by
Ar.sup.1 is usually 4-60, preferably 4-30, more preferably 5-22 and
most preferably 5-12, not including the number of carbon atoms of
substituents. The unsubstituted or substituted divalent aromatic
heterocyclic group may be an unsubstituted or substituted
pyridinediyl group such as 2,5-pyridinediyl or 2,6-pyridinediyl, an
unsubstituted or substituted furanediyl group such as
2,5-furanediyl, an unsubstituted or substituted quinolinediyl group
such as 2,6-quinolinediyl, an unsubstituted or substituted
isoquinolinediyl group such as 1,4-isoquinolinediyl or
1,5-isoquinolinediyl, an unsubstituted or substituted
quinoxalinediyl group such as 5,8-quinoxalinediyl, an unsubstituted
or substituted carbazolediyl group such as 2,7-carbazolediyl or
3,6-carbazolediyl, an unsubstituted or substituted phenoxazinediyl
group such as 3,7-phenoxazinediyl, an unsubstituted or substituted
phenothiazinediyl group such as 3,7-phenothiazinediyl, an
unsubstituted or substituted dibenzosiloldiyl group such as
2,7-dibenzosiloldiyl, an unsubstituted or substituted thiophenydiyl
group such as 2,5-thiophendiyl, an unsubstituted or substituted
dibenzoborol group such as 3, 7-dibenzoboroldiyl, preferably an
unsubstituted or substituted carbazolediyl or unsubstituted or
substituted phenoxazinediyl group, and more preferably an
unsubstituted or substituted phenoxazinediyl group.
[0058] When the aforementioned arylene or divalent aromatic
heterocyclic group has a substituent, the substituent is preferably
an unsubstituted or substituted alkyl, unsubstituted or substituted
alkoxy, unsubstituted or substituted aryl, unsubstituted or
substituted aryloxy, unsubstituted or substituted monovalent
heterocyclic, unsubstituted or substituted amino, unsubstituted or
substituted silyl, halogen, unsubstituted alkoxycarbonyl,
unsubstituted carboxyl or cyano group, and more preferably an
unsubstituted alkyl, unsubstituted alkoxy, unsubstituted aryl,
unsubstituted alkylaryl, unsubstituted alkoxyaryl or unsubstituted
alkoxycarbonylaryl group.
[0059] The definitions and examples of unsubstituted or substituted
alkyl groups that may serve as substituents above are the same
definitions and examples for the unsubstituted or substituted alkyl
groups represented by R.sup.5 and R.sup.6.
[0060] The definitions and examples of unsubstituted or substituted
alkoxy, unsubstituted or substituted aryl, unsubstituted or
substituted aryloxy, unsubstituted or substituted monovalent
heterocyclic, unsubstituted or substituted amino, unsubstituted or
substituted silyl, halogen and alkoxycarbonyl groups that may serve
as substituents are the same definitions and examples for the
unsubstituted or substituted alkoxy, unsubstituted or substituted
aryl, unsubstituted or substituted aryloxy, unsubstituted or
substituted monovalent heterocyclic, unsubstituted or substituted
amino, unsubstituted or substituted silyl, halogen and
alkoxycarbonyl groups represented by R.sup.3 and R.sup.4.
[0061] From the viewpoint of extending the luminance lifetime of
the obtained light emitting device, the constitutional unit
represented by formula (6) is preferably a constitutional unit
represented by formula (8), (9) or (10).
##STR00029##
(In the formula (8), R.sup.9 represents an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonylaryl group.
The letter f represents an integer of 0-4. Multiple R.sup.9 groups
may be the same or different. In the formula (9), R.sup.10 and
R.sup.11 each independently represent an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkoxyaryl
or unsubstituted alkoxycarbonylaryl group. In the formula (10),
R.sup.12 represents an unsubstituted alkyl, unsubstituted aryl,
unsubstituted alkylaryl, unsubstituted alkoxyaryl or unsubstituted
alkoxycarbonylaryl group. X is a single bond, --O--, --S-- or
--C(R.sup.C).sub.2--. R.sup.C represents an unsubstituted alkyl,
unsubstituted aryl, unsubstituted alkylaryl or unsubstituted
alkoxyaryl group, and the two R.sup.C groups may be the same or
different.)
[0062] In formula (8), R.sup.9 represents an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonylaryl group,
preferably an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted alkylaryl or unsubstituted alkoxyaryl group, more
preferably an unsubstituted alkyl or unsubstituted alkoxy group and
most preferably an unsubstituted alkyl group. The definitions and
examples of unsubstituted alkyl groups represented by R.sup.9 are
the same as the definitions and examples of unsubstituted alkyl
groups represented by R.sup.1 and R.sup.2.
[0063] The unsubstituted alkoxy group represented by R.sup.9 may be
straight-chain, branched or cyclic, and the number of carbon atoms
is usually 1-20, preferably 1-15 and more preferably 4-10.
Unsubstituted alkoxy groups include methoxy, ethoxy, n-propyloxy,
isopropyloxy, n-butyloxy, isobutyloxy, tert-butyloxy, n-pentyloxy,
n-hexyloxy, cyclohexyloxy, n-heptyloxy, n-octyloxy,
2-ethylhexyloxy, n-nonyloxy, n-decyloxy, 3,7-dimethyloctyloxy and
lauryloxy, and from the viewpoint of improving balance between
solubility of the polymer compound in organic solvents and heat
resistance, n-butyloxy, n-pentyloxy, n-hexyloxy, n-octyloxy,
2-ethylhexyloxy, n-decyloxy and 3,7-dimethyloctyloxy groups are
preferred.
[0064] The number of carbon atoms of the unsubstituted aryl group
represented by R.sup.9 is usually 6-60, preferably 6-48, more
preferably 6-20 and even more preferably 6-10. Unsubstituted aryl
groups include phenyl, 1-naphthyl, 2-naphthyl, 1-anthracenyl,
2-anthracenyl, 9-anthracenyl, 1-pyrenyl, 2-pyrenyl, 4-pyrenyl,
2-perylenyl, 3-perylenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl,
1-biphenylenyl, 2-biphenylenyl, 2-phenanthrenyl, 9-phenanthrenyl,
2-phenylphenyl, 3-phenylphenyl and 4-phenylphenyl groups.
[0065] An unsubstituted alkylaryl group represented by R.sup.9 is
an unsubstituted aryl group represented by R.sup.9 substituted with
an unsubstituted alkyl group represented by R.sup.9, and for
example, this includes 2-methylphenyl, 3-methylphenyl,
4-methylphenyl, 3-n-butylphenyl, 4-n-butylphenyl,
4-tert-butylphenyl, 3-n-hexylphenyl, 4-n-hexylphenyl,
4-n-octylphenyl, 3,5-dimethylphenyl, 4-n-butyl-2,6-dimethylphenyl
and 4-tert-butyl-2,6-dimethylphenyl, among which 3-n-butylphenyl,
4-n-butylphenyl, 4-tert-butylphenyl, 3-n-hexylphenyl,
4-n-hexylphenyl, 4-n-octylphenyl, 4-n-butyl-2,6-dimethylphenyl and
4-tert-butyl-2,6-dimethylphenyl are preferred.
[0066] An unsubstituted alkoxyaryl group represented by R.sup.9 is
an unsubstituted aryl group represented by R.sup.9 substituted with
an unsubstituted alkoxy group represented by R.sup.9, and for
example, this includes 2-methoxyphenyl, 3-methoxyphenyl,
4-methoxyphenyl, 4-n-butyloxyphenyl, 3-n-hexyloxyphenyl,
4-n-hexyloxyphenyl and 4-n-octyloxyphenyl, among which
4-n-butyloxyphenyl, 3-n-hexyloxyphenyl and 4-n-hexyloxyphenyl are
preferred.
[0067] An unsubstituted alkoxycarbonylaryl group represented by
R.sup.9 is an unsubstituted aryl group represented by R.sup.9
substituted with an unsubstituted alkoxycarbonyl group represented
by R.sup.3 or R.sup.4, and for example, this includes
2-methoxycarbonylphenyl, 3-methoxycarbonylphenyl,
4-methoxycarbonylphenyl, 3-ethoxycarbonylphenyl,
4-ethoxycarbonylphenyl, 3-n-butoxycarbonylphenyl and
4-n-butoxycarbonylphenyl, among which 3-ethoxycarbonylphenyl and
4-ethoxycarbonylphenyl are preferred.
[0068] In formula (8), f represents an integer of 0-4, and it
preferably represents an integer of 0-2.
[0069] Constitutional units represented by formula (8) include
constitutional units represented by formulas (1K-1)-(1K-9) and
formulas (1L-1)-(1L-12).
##STR00030## ##STR00031## ##STR00032## ##STR00033##
[0070] In formula (9), R.sup.10 and R.sup.11 each independently
represent an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkoxyaryl or unsubstituted
alkoxycarbonylaryl group.
[0071] The unsubstituted alkyl, unsubstituted alkoxy, unsubstituted
aryl, unsubstituted alkoxyaryl and unsubstituted alkoxycarbonylaryl
groups represented by R.sup.10 and R.sup.11 have the same
definitions and examples as the unsubstituted alkyl, unsubstituted
alkoxy, unsubstituted aryl, unsubstituted alkoxyaryl and
unsubstituted alkoxycarbonylaryl groups represented by R.sup.9 in
formula (8).
[0072] Constitutional units represented by formula (9) include
constitutional units represented by formulas (1M-1)-(1M-18).
##STR00034## ##STR00035## ##STR00036## ##STR00037##
[0073] In formula (10), R.sup.12 represents an unsubstituted alkyl,
unsubstituted aryl, alkylaryl, unsubstituted alkoxyaryl or
unsubstituted alkoxycarbonylaryl group. The definitions and
examples of unsubstituted alkyl, unsubstituted aryl, unsubstituted
alkylaryl, unsubstituted alkoxyaryl and unsubstituted
alkoxycarbonylaryl groups are the same as the definitions and
examples of unsubstituted alkyl, unsubstituted aryl, unsubstituted
alkylaryl, unsubstituted alkoxyaryl and unsubstituted
alkoxycarbonylaryl groups represented by R.sup.9 in formula
(8).
[0074] In formula (10), X is a single bond, --O--, --S-- or
--C(R.sup.C).sub.2--, preferably --O-- or --S--, and more
preferably --O--. R.sup.C represents an unsubstituted alkyl,
unsubstituted aryl, unsubstituted alkylaryl or unsubstituted
alkoxyaryl group. The definitions and examples of unsubstituted
alkyl, unsubstituted aryl, unsubstituted alkylaryl and
unsubstituted alkoxyaryl groups are the same as the definitions and
examples of unsubstituted alkyl, unsubstituted aryl, unsubstituted
alkylaryl and unsubstituted alkoxyaryl groups represented by
R.sup.9 in formula (8).
[0075] Constitutional units represented by formula (10) include
constitutional units represented by formulas (1N-1)-(1N-17).
##STR00038## ##STR00039## ##STR00040## ##STR00041##
[0076] In formula (7), Ar.sup.2, Ar.sup.3 and Ar.sup.4 each
independently represent an unsubstituted or substituted arylene
group, an unsubstituted or substituted divalent aromatic
heterocyclic group, or an unsubstituted or substituted divalent
group linked to two aromatic rings by single bonds.
[0077] The number of carbon atoms of the unsubstituted or
substituted arylene group represented by Ar.sup.2, Ar.sup.3 and
Ar.sup.4 is usually 6-60, preferably 6-30, more preferably 6-18,
even more preferably 6-10 and most preferably 6, not including the
number of carbon atoms of substituents. Examples of unsubstituted
arylene groups include phenylene groups such as 1,3-phenylene and
1,4-phenylene, naphthalenediyl groups such as 1,4-naphthalenediyl
and 2,6-naphthalenediyl, anthracenediyl groups such as
9,10-anthracenediyl, phenanthrenediyl groups such as
2,7-phenanthrenediyl, naphthacenediyl groups such as
5,12-naphthacenediyl, fluorenediyl groups such as 2,7-fluorenediyl,
perylenediyl groups such as 3,8-perylenediyl and chrysenediyl
groups such as 2,8-chrysenediyl and 6,12-chrysenediyl.
[0078] The number of carbon atoms of the unsubstituted or
substituted divalent heterocyclic groups represented by Ar.sup.2,
A.sup.3 and Ar.sup.4 is usually 4-60, preferably 4-20, more
preferably 4-9 and even more preferably 4 or 5, not including the
number of carbon atoms of substituents. Unsubstituted divalent
heterocyclic groups include pyrrolediyl groups such as
N-methyl-2,5-pyrrolediyl, furanediyl groups such as 2,5-furanediyl,
pyridinediyl groups such as 2,5-pyridinediyl and 2,6-pyridinediyl,
quinolinediyl groups such as 2,4-quinolinediyl and
2,6-quinolinediyl, isoquinolinediyl groups such as
1,4-isoquinolinediyl and 1,5-isoquinolinediyl, phenoxazinediyl
groups such as 3,7-phenoxazinediyl and carbazolediyl groups such as
3,6-carbazolediyl.
[0079] Unsubstituted divalent groups having two aromatic rings
linked thereto by single bonds, represented by Ar.sup.2, Ar.sup.3
and Ar.sup.4, include groups represented by formulas (7A-1)-(7A-4),
preferably groups represented by formulas (7A-1)-(7A-3) and more
preferably groups represented by formula (7A-1).
##STR00042##
[0080] When Ar.sup.2, Ar.sup.3 and Ar.sup.4 have substituents, the
substituents are preferably unsubstituted or substituted alkyl,
unsubstituted or substituted alkoxy, unsubstituted or substituted
aryl, unsubstituted or substituted aryloxy, unsubstituted or
substituted monovalent heterocyclic, unsubstituted or substituted
amino, unsubstituted or substituted silyl, halogen, unsubstituted
alkoxycarbonyl, unsubstituted carboxyl or cyano groups, more
preferably unsubstituted alkyl, unsubstituted alkoxy, unsubstituted
aryl, unsubstituted alkylaryl, unsubstituted alkoxyaryl or
unsubstituted alkoxycarbonylaryl groups, and even more preferably
unsubstituted alkyl or unsubstituted alkylaryl groups.
[0081] The definitions and examples of unsubstituted or substituted
alkyl groups are the same definitions and examples for the
unsubstituted or substituted alkyl groups represented by R.sup.5
and R.sup.6.
[0082] The definitions and examples of unsubstituted or substituted
alkoxy, unsubstituted or substituted aryl, unsubstituted or
substituted aryloxy, unsubstituted or substituted monovalent
heterocyclic, unsubstituted or substituted amino, unsubstituted or
substituted silyl, halogen and unsubstituted alkoxycarbonyl groups
are each the same as the definitions and examples of unsubstituted
or substituted alkoxy, unsubstituted or substituted aryl,
unsubstituted or substituted aryloxy, unsubstituted or substituted
monovalent heterocyclic, unsubstituted or substituted amino,
unsubstituted or substituted silyl, halogen and unsubstituted
alkoxycarbonyl groups represented by R.sup.3 and R.sup.4.
[0083] Ar.sup.2 and Ar.sup.3 are preferably unsubstituted or
substituted arylene groups, more preferably unsubstituted or
substituted 1,3-phenylene, unsubstituted or substituted
1,4-phenylene, unsubstituted or substituted 1,4-naphthalenediyl or
unsubstituted or substituted 2,6-naphthalenediyl groups, even more
preferably unsubstituted or substituted 1,4-phenylene or
unsubstituted or substituted 1,4-naphthalenediyl groups, and most
preferably unsubstituted or substituted 1,4-phenylene groups.
[0084] Ar.sup.4 is preferably an unsubstituted or substituted
arylene group or an unsubstituted or substituted divalent group
having two aromatic rings linked by single bonds, more preferably
an unsubstituted or substituted 1,3-phenylene, unsubstituted or
substituted 1,4-phenylene, unsubstituted or substituted
1,4-naphthalenediyl, unsubstituted or substituted 2,7-fluorenediyl,
unsubstituted or substituted 9,10-anthracenediyl or unsubstituted
or substituted 6,12-chrysenediyl group, or an unsubstituted or
substituted group represented by formula (7A-1) above, even more
preferably an unsubstituted or substituted 1,4-phenylene,
unsubstituted or substituted 1,4-naphthalenediyl, unsubstituted or
substituted 2,7-fluorenediyl or 9,10-anthracenediyl group, or an
unsubstituted or substituted group represented by formula (7A-1),
and yet more preferably an unsubstituted 1,4-phenylene or
substituted 2,7-fluorenediyl group, or an unsubstituted group
represented by formula (7A-1).
[0085] R.sup.A and R.sup.B in formula (7) each independently
represent hydrogen, an unsubstituted or substituted alkyl group, an
unsubstituted or substituted aryl group, or an unsubstituted or
substituted monovalent heterocyclic group. The definitions and
examples of unsubstituted or substituted alkyl groups are the same
definitions and examples for the unsubstituted or substituted alkyl
groups represented by R.sup.5 and R.sup.6. The definitions and
examples of unsubstituted or substituted aryl and unsubstituted or
substituted monovalent heterocyclic groups are each the same as the
definitions and examples of unsubstituted or substituted aryl and
unsubstituted or substituted monovalent heterocyclic groups
represented by R.sup.3 and R.sup.4.
[0086] In formula (7), e is 0 or 1 and preferably 1.
[0087] From the viewpoint of the luminance lifetime of the obtained
light emitting device, the constitutional unit represented by
formula (7) is preferably a constitutional unit represented by
formula (14).
##STR00043##
(In the formula, Ar.sup.4 has the same meaning as above. R.sup.D
and R.sup.E each independently represent an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonyl group. The
letters h and i each independently represent an integer of 0-5.
When multiple R.sup.D and R.sup.E groups are present, they may be
the same or different. The letter e has the same meaning as
above.)
[0088] In formula (14), R.sup.D and R.sup.E each independently
represent an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl or unsubstituted alkoxycarbonyl group.
[0089] The definitions and examples of unsubstituted alkyl groups
are the same as the definitions and examples of unsubstituted alkyl
groups represented by R.sup.1 and R.sup.2.
[0090] The definitions and examples of unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl and unsubstituted
alkoxyaryl groups are the same as the definitions and examples of
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl
and unsubstituted alkoxyaryl groups represented by R.sup.9 in
formula (8).
[0091] The definitions and examples of unsubstituted alkoxycarbonyl
groups are the same as the definitions and examples of
unsubstituted alkoxycarbonyl groups represented by R.sup.3 and
R.sup.4 in formula (1).
[0092] In formula (14), h and i each independently represent an
integer of 0-5, preferably represent an integer of 1-3, and even
more preferably represent 1 or 3.
[0093] Constitutional units represented by formula (14) include
constitutional units represented by formulas (1Q-1)-(1Q-30).
##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048##
##STR00049##
[0094] The polymer compound of the invention preferably comprises
at least one constitutional unit selected from the group consisting
of constitutional units represented by formula (11), constitutional
units represented by formula (12) and constitutional units
represented by formula (13), and more preferably it comprises a
constitutional unit represented by formula (13), so that the
driving voltage of the obtained light emitting device will be
favorable.
##STR00050##
(In the formula (11), R.sup.13 and R.sup.13' each independently
represent hydrogen or an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl or unsubstituted alkoxycarbonylaryl group.
[0095] In the formula (12), R.sup.14, R.sup.15, R.sup.16, R.sup.17,
R.sup.18 and R.sup.19 each independently represent hydrogen or an
unsubstituted alkyl, unsubstituted alkoxy, unsubstituted aryl,
unsubstituted alkylaryl, unsubstituted alkoxyaryl or unsubstituted
alkoxycarbonylaryl group.
In the formula (13), R.sup.20 represents an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, alkylaryl, unsubstituted
alkoxyaryl or unsubstituted alkoxycarbonylaryl group. The letter g
represents an integer of 0-5. Multiple R.sup.20 groups may be the
same or different.)
[0096] In formula (11), R.sup.13 and R.sup.13' each independently
represent hydrogen or an unsubstituted alkyl, unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl or unsubstituted alkoxycarbonylaryl group.
[0097] The definitions and examples of unsubstituted alkyl groups
are the same as the definitions and examples of unsubstituted alkyl
groups represented by R.sup.1 and R.sup.2.
[0098] The definitions and examples of unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl and unsubstituted alkoxycarbonylaryl groups are the same
as the definitions and examples of unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl and unsubstituted alkoxycarbonylaryl groups represented
by R.sup.9 in formula (8).
[0099] Constitutional units represented by formula (11) include
constitutional units represented by formulas (1S-1)-(1S-7).
##STR00051## ##STR00052##
[0100] In formula (12), R.sup.14, R.sup.15, R.sup.16, R.sup.17,
R.sup.18 and R.sup.19 each independently represent hydrogen or an
unsubstituted alkyl, unsubstituted alkoxy, unsubstituted aryl,
unsubstituted alkylaryl, unsubstituted alkoxyaryl or unsubstituted
alkoxycarbonylaryl group.
[0101] The definitions and examples of unsubstituted alkyl groups
are the same as the definitions and examples of unsubstituted alkyl
groups represented by R.sup.1 and R.sup.2.
[0102] The definitions and examples of unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl and unsubstituted alkoxycarbonylaryl groups are the same
as the definitions and examples of unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl and unsubstituted alkoxycarbonylaryl groups represented
by R.sup.9 in formula (8).
[0103] Constitutional units represented by formula (12) include
constitutional units represented by formulas (1T-1)-(1T-8).
##STR00053## ##STR00054##
[0104] In formula (13), R.sup.20 represents an unsubstituted alkyl,
unsubstituted alkoxy, unsubstituted aryl, unsubstituted alkylaryl,
unsubstituted alkoxyaryl or unsubstituted alkoxycarbonylaryl
group.
[0105] The definitions and examples of unsubstituted alkyl groups
are the same as the definitions and examples of unsubstituted alkyl
groups represented by R.sup.1 and R.sup.2.
[0106] The definitions and examples of unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl and unsubstituted alkoxycarbonylaryl groups are the same
as the definitions and examples of unsubstituted alkoxy,
unsubstituted aryl, unsubstituted alkylaryl, unsubstituted
alkoxyaryl and unsubstituted alkoxycarbonylaryl groups represented
by R.sup.9 in formula (8).
[0107] In formula (13), g represents an integer of 0-5, preferably
an integer of 1-3, and more preferably 1.
[0108] Constitutional units represented by formula (13) include
constitutional units represented by formulas (1R-1)-(1R-6).
##STR00055## ##STR00056##
[0109] In particular, the polymer compound of the present
embodiment is preferably a polymer compound comprising a
constitutional unit represented by formula (1), and one or more
constitutional units selected from the group consisting of
constitutional units represented by formula (8), constitutional
units represented by formula (9), constitutional units represented
by formula (10) and constitutional units represented by formula
(14).
[0110] In that case, the total number of moles of constitutional
units represented by formula (1), constitutional units represented
by formula (8), constitutional units represented by formula (9),
constitutional units represented by formula (10) and constitutional
units represented by formula (14) in the polymer compound of the
invention is preferably 80-100%, more preferably 90-100% and even
more preferably 95-100%, with respect to the total number of moles
of all of the constitutional units.
[0111] In particular, as such a polymer compound, a polymer
compound comprising one or more constitutional units represented by
formula (1), one or more constitutional units represented by
formula (9), and one or more constitutional units represented by
formula (10), a polymer compound comprising one or more
constitutional units represented by formula (1), one or more
constitutional units represented by formula (9), and one or more
constitutional units represented by formula (14), a polymer
compound comprising one or more constitutional units represented by
formula (1), one or more constitutional units represented by
formula (10), and one or more constitutional units represented by
formula (14), or a polymer compound comprising one or more
constitutional units represented by formula (1), one or more
constitutional units represented by formula (9), one or more
constitutional units represented by formula (10), and one or more
constitutional units represented by formula (14) is preferable.
[0112] Especially, a polymer compound comprising one or more
constitutional units represented by formula (1), one or more
constitutional units represented by formula (9), and one or more
constitutional units represented by formula (10), or a polymer
compound comprising one or more constitutional units represented by
formula (1), one or more constitutional units represented by
formula (9), one or more constitutional units represented by
formula (10), and one or more constitutional units represented by
formula (14) is more preferable.
[0113] Furthermore, the polymer compound of the present embodiment
is also preferably a polymer compound comprising a constitutional
unit represented by formula (1), one or more constitutional units
selected from the group consisting of constitutional units
represented by formula (8), constitutional units represented by
formula (9), constitutional units represented by formula (10) and
constitutional units represented by formula (14), and one or more
constitutional units selected from the group consisting of
constitutional units represented by formula (11), constitutional
units represented by formula (12), and constitutional units
represented by formula (13).
[0114] As such, in case the polymer compound includes one or more
constitutional units selected from the group consisting of
constitutional units represented by formula (11), constitutional
units represented by formula (12), and constitutional units
represented by formula (13), the total number of moles of
constitutional units represented by formula (1), one or more
constitutional units selected from the group consisting of
constitutional units represented by formula (9), constitutional
units represented by formula (10), and constitutional units
represented by formula (14), and one or more constitutional units
selected from the group consisting of constitutional units
represented by formula (11), constitutional units represented by
formula (12), and constitutional units represented by formula (13)
is preferably 80-100%, more preferably 90-100% and even more
preferably 95-100%, with respect to the total number of moles of
all of the constitutional units.
[0115] As a polymer compound in this case, a polymer compound
consisting of one or more constitutional units represented by
formula (1), one or more constitutional units represented by
formula (8), and one or more constitutional units represented by
formula (13), or a polymer compound consisting of one or more
constitutional units represented by formula (1), one or more
constitutional units represented by formula (8), one or more
constitutional units represented by formula (14), and one or more
constitutional units represented by formula (13) is more
preferable. In particular, a polymer compound consisting of one or
more constitutional units represented by formula (1), one or more
constitutional units represented by formula (8), and one or more
constitutional units represented by formula (13) is further more
preferable.
[0116] The polystyrene equivalent number-average molecular weight
(Mn) of the polymer compound of the present embodiment, as measured
by gel permeation chromatography (hereinafter, "GPC") will usually
be 1.times.10.sup.3-1.times.10.sup.8 and is preferably
1.times.10.sup.4-1.times.10.sup.6. In addition, the polystyrene
equivalent weight-average molecular weight (Mw) of the polymer
compound of the invention will usually be
1.times.10.sup.3-1.times.10.sup.8, and from the viewpoint of
obtaining favorable film formability, it is preferably
1.times.10.sup.4-5.times.10.sup.6, more preferably
3.times.10.sup.4-1.times.10.sup.6 and even more preferably
5.times.10.sup.4-5.times.10.sup.5.
[0117] If the end groups of the polymer compound of the present
embodiment remain as polymerizing active groups, the luminescence
property and usable life may potentially be reduced when the
polymer compound is used to fabricate a light emitting device, and
therefore stable groups are preferred as the end groups. The end
groups are preferably groups that have conjugated bonds with the
main chain, and these include groups bonded to aryl or monovalent
heterocyclic groups via carbon-carbon bonds (specifically, the
substituents denoted by formula 10 of Japanese Unexamined Patent
Application Publication HEI No. 9-45478).
[0118] The polymer compound of the present embodiment may be a
block copolymer, random copolymer, alternating copolymer or graft
copolymer, or it may even be in another form.
[0119] The following polymer compounds (P-1)-(P-11) may be
mentioned as preferable polymer compounds of the invention. For
example, polymer compound (P-1) is a copolymer comprising a
constitutional unit represented by formula (4) and a constitutional
unit represented by formula (5) in the molar ratio Q1:Q2, and
polymer compounds (P-2)-(P-11) are similar. Here, R.sup.3, R.sup.4,
R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, R.sup.12, R.sup.13,
R.sup.13', R.sup.20, R.sup.D, R.sup.E, Ar.sup.4, a1, b1, e, f, g, h
and i have the same meaning as above. Also, Q1-Q29 are numbers
satisfying the following formulas attached to the chemical formulas
indicating each compound.
##STR00057## ##STR00058## ##STR00059## ##STR00060##
[0120] A specific example of the polymer compound of the present
embodiment include the polymer compound (PA-1)-(PA-13) below.
##STR00061## ##STR00062## ##STR00063## ##STR00064##
##STR00065##
[0121] <Method for Producing Polymer Compound>
A preferred method for producing the polymer compound of the
invention will now be described.
[0122] The polymer compound of the invention may be produced, for
example, by condensation polymerization of a compound represented
by formula (a).
##STR00066##
(In the formula, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5,
R.sup.6, a and b have the same meaning as above. Y.sup.1 is a
halogen atom, methoxy group, boric acid ester residue, boric acid
residue (that is, --B(OH).sub.2), a group represented by formula
(a-1), a group represented by formula (a-2), a group represented by
formula (a-3) or a group represented by formula (a-4). Two Y.sup.1
groups when present may be the same or different.)
##STR00067##
(In the formula (a-1)-(a-4), R.sup.T represents an unsubstituted or
substituted alkyl or unsubstituted or substituted aryl group, and
X.sub.A represents a halogen atom.)
[0123] When the polymer compound of the invention comprises a
constitutional unit represented by formula (6) and a constitutional
unit represented by formula (7), the polymer compound can be
produced, for example, by condensation polymerization of a compound
represented by formula (a), and at least one compound selected from
the group consisting of compounds represented by formula (b-1) and
compounds represented by formula (b-2).
##STR00068##
(In the formula (b-1) and (b-2), Ar.sup.1, Ar.sup.2, Ar.sup.3,
Ar.sup.4, R.sup.A, R.sup.B, Y.sup.1 and e have the same meaning as
above.)
[0124] In formulas (a), (b-1), (b-2), (a-2) and (a-3), the halogen
atoms represented by Y.sup.1 and X.sub.A may be chlorine, bromine
or iodine.
[0125] In formulas (a), (b-1) and (b-2), the boric acid ester
residue represented by Y.sup.1 may be a group represented by the
following formula.
##STR00069##
[0126] The definitions and examples of unsubstituted alkyl groups
represented by R.sup.T in formula (a-1) are the same as the
definitions and examples of unsubstituted alkyl groups represented
by R.sup.1 and R.sup.2. The definitions and examples of substituted
alkyl groups in formula (a-1) are the same as the definitions and
examples of substituted alkyl groups represented by R.sup.5 and
R.sup.6.
[0127] The definitions and examples of unsubstituted or substituted
aryl groups in formula (a-1) are the same definitions and examples
for the unsubstituted or substituted aryl groups represented by
R.sup.3 and R.sup.4.
[0128] Examples of sulfonate groups represented by formula (a-1)
include methane sulfonate, trifluoromethane sulfonate, phenyl
sulfonate and 4-methylphenyl sulfonate groups.
[0129] The definitions and examples of unsubstituted or substituted
alkyl and unsubstituted or substituted aryl groups represented by
R.sup.T in formula (a-4) are the same definitions and examples
mentioned for unsubstituted or substituted alkyl and unsubstituted
or substituted aryl groups represented by R.sup.T in formula
(a-1).
[0130] Groups represented by formula (a-4) include
trimethylstannanyl, triethylstannanyl and tributylstannanyl
groups.
[0131] The compounds represented by formulas (a), (b-1) and (b-2)
may be synthesized and isolated beforehand, or they may be prepared
in the reaction system and used directly.
[0132] In formulas (a), (b-1) and (b-2), Y.sup.1 is preferably a
halogen atom, boric acid ester residue or boric acid residue, since
the convenience of synthesis and ease of handling of the compound
represented by formula (a), (b-1) or (b-2) will be improved.
[0133] The method of condensation polymerization may be a method of
reaction of a compound represented by formula (a), (b-1) or (b-2),
using an appropriate catalyst and an appropriate base.
[0134] Such catalysts include transition metal complexes which may
be palladium complexes such as palladium
[tetrakis(triphenylphosphine)],
[tris(dibenzylideneacetone)]dipalladium and palladium acetate or
nickel complexes such as nickel [tetrakis(triphenylphosphine)],
[1,3-bis(diphenylphosphino)propane]dichloronickel and
[bis(1,4-cyclooctadiene)]nickel, or catalysts further comprising
ligands such as triphenylphosphine, tri(tert-butylphosphine),
tricyclohexylphosphine, diphenylphosphinopropane or pipyridyl as
necessary. The catalyst may be synthesized beforehand or prepared
in the reaction system and used directly. These catalysts may be
used alone or in combinations of two or more.
[0135] When a catalyst is used, the amount of use is preferably
0.00001-3 mol equivalents, more preferably 0.00005-0.5 mol
equivalents and even more preferably 0.0001-0.2 mol equivalents, as
the amount of transition metal with respect to the total number of
moles of the compound represented by formula (a), (b-1) or
(b-2).
[0136] Examples of the aforementioned bases include inorganic bases
such as sodium carbonate, potassium carbonate, cesium carbonate,
potassium fluoride, cesium fluoride and tripotassium phosphate, and
organic bases such as tetrabutylammonium fluoride,
tetrabutylammonium chloride, tetrabutylammonium bromide and
tetrabutylammonium hydroxide. These bases may be used alone or in
combinations of two or more.
[0137] When a base is used, the amount of use is preferably 0.5-20
mol equivalents and more preferably 1-10 mol equivalents with
respect to the total number of moles of the compound represented by
formula (a), (b-1) or (b-2).
[0138] The condensation polymerization may be conducted in the
presence of a solvent such as an organic solvent.
[0139] The preferable organic solvent will differ depending on the
type of compound represented by formula (a), (b-1) or (b-2) and the
reaction, and examples include toluene, xylene, mesitylene,
tetrahydrofuran, 1,4-dioxane, dimethoxyethane,
N,N-dimethylacetamide and N,N-dimethylformamide. In order to
inhibit secondary reactions, such solvents are preferably subjected
to deoxidizing treatment. These organic solvents may be used alone
or in combinations of two or more.
[0140] The amount of organic solvent used is such that the total
concentration of the compound represented by formula (a), (b-1) or
(b-2) is usually 0.1-90 wt %, preferably 1-50 wt % and more
preferably 2-30 wt %.
[0141] The reaction temperature for the condensation polymerization
is preferably -100-200.degree. C., more preferably -80-150.degree.
C. and even more preferably 0-120.degree. C. The reaction time will
depend on the conditions such as the reaction temperature, but it
will usually be at least 1 hour, and is preferably 2-500 hours.
[0142] The condensation polymerization is preferably conducted
under anhydrous conditions when Y.sup.1 in formula (a), (b-1) or
(b-2) is a group represented by formula (a-2), for example.
[0143] The method of condensation polymerization may be a method of
polymerization by Suzuki reaction (Chem. Rev. Vol. 95, p. 2457
(1995)), a method of polymerization by Grignard reaction (Kobunshi
Kinou Zairyo Series Vol. 2, "Polymer Syntheses and Reactions (2),
p. 432-433, Kyoritsu Publishing), or a method of polymerization by
Yamamoto polymerization (Prog. Polym. Sci., Vol. 17, p. 1153-1205,
1992).
[0144] Post-treatment after condensation polymerization may be
carried out by a known method, such as adding the reaction mixture
obtained by condensation polymerization to a lower alcohol such as
methanol and filtering and drying the deposited precipitate.
[0145] Such post-treatment can yield a polymer compound of the
invention, but if the purity of the polymer compound is low it may
be purified by common methods such as recrystallization, continuous
extraction with a Soxhlet extractor, or column chromatography.
[0146] <Composition>
The first composition of the preferable embodiment comprises at
least one material selected from the group consisting of hole
transport materials, electron transport materials and luminescent
materials, and a polymer compound according to the invention. Such
a composition can be used as a charge transport material or
luminescent material, for example.
[0147] Hole transport materials, electron transport materials and
luminescent materials include hole transport materials, electron
transport materials and luminescent materials which may be present
in the organic layers of light emitting devices, as described
hereunder.
[0148] The content ratio of the polymer compound of the invention
and at least one material selected from the group consisting of
hole transport materials, electron transport materials and
luminescent materials will depend on the purpose of use, but for
example, for a luminescent material the polymer compound of the
invention is usually used at 20-99 parts by weight and preferably
40-95 parts by weight with respect to 100 parts by weight of the
entire composition.
[0149] The polystyrene equivalent number-average molecular weight
of the first composition of the invention will usually be
1.times.10.sup.3-1.times.10.sup.8 and is preferably
1.times.10.sup.4-1.times.10.sup.6. The polystyrene equivalent
weight-average molecular weight of this composition of the
invention will usually be 1.times.10.sup.3-1.times.10.sup.8, and
from the viewpoint of obtaining favorable film formability and the
luminous efficiency of the obtained device, it is preferably
1.times.10.sup.4-5.times.10.sup.6. The average molecular weight of
the composition of the invention is the value obtained by GPC
analysis of the composition.
[0150] The second composition of the invention is a composition
comprising a polymer compound of the invention and a solvent. Such
a composition is often referred to as "solution", "ink" or "ink
composition", and will hereunder be referred to as "solution of the
invention".
[0151] The solution of the invention is useful for fabrication of
devices by coating, such as in ink jet printing or press printing.
In addition to the polymer compound and solvents, the solvent of
the invention may also contain hole transport materials, electron
transport materials, luminescent materials, stabilizers, thickeners
(high molecular weight compounds or poor solvents for increased
viscosity), low-molecular-weight compounds to lower the viscosity,
surfactants (to lower the surface tension), antioxidants and the
like.
[0152] The proportion of the polymer compound of the invention in
the solution of the invention will usually be 0.1-99.9 parts by
weight, and is preferably 0.1-10 parts by weight, more preferably
0.2-7 parts by weight and even more preferably 0.5-2 parts by
weight, with respect to 100 parts by weight of the solution.
[0153] The viscosity of the solution of the invention may be
adjusted depending on the type of printing method, but when the
solution is to be passed through a discharge apparatus as in ink
jet printing, the viscosity is preferably in the range of 1-20 mPas
at 25.degree. C. to prevent clogging or curving trajectory of the
ink during discharge.
[0154] The high molecular weight compound used as the thickener may
be any one that is soluble in the same solvent as the polymer
compound of the invention and does not inhibit luminescence or
charge transport, and for example, a high molecular weight
polystyrene or high molecular weight polymethyl methacrylate may be
used. These high molecular weight compounds preferably have
polystyrene equivalent weight-average molecular weights of 500,000
or greater and more preferably 1,000,000 or greater.
[0155] A poor solvent may be used as the thickener. The viscosity
can be increased by adding a small amount of a poor solvent for the
solid portion in the solution. When a poor solvent is added for
this purpose, the type and amount of solvent may be selected in a
range so that the solid portion in the solution is not deposited.
In consideration of stability during storage, the amount of poor
solvent is preferably no greater than 50 parts by weight and even
more preferably no greater than 30 parts by weight with respect to
100 parts by weight of the total solution.
[0156] The antioxidant is used to improve the storage stability of
the solution of the invention. The antioxidant may be, for example,
a phenol-based antioxidant, phosphorus-based antioxidant or the
like, so long as it is soluble in the same solvent as the polymer
compound of the invention and does not inhibit luminescence or
charge transport.
[0157] The solvent in the solution of the invention is preferably
one that can dissolve or evenly disperse the solid components in
the solution. The solvent may be a chlorine-based solvent such as
chloroform, methylene chloride, 1,2-dichloroethane,
1,1,2-trichloroethane, chlorobenzene or o-dichlorobenzene, an
ether-based solvent such as tetrahydrofuran, dioxane, anisole, or
4-methylanisole, an aromatic hydrocarbon-based solvent such as
toluene, xylene, mesitylene, ethylbenzene, n-hexylbenzene, or
cyclohexylbenzene, an aliphatic hydrocarbon-based solvent such as
cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptane,
n-octane, n-nonane or n-decane, a ketone-based solvent such as
acetone, methyl ethyl ketone, cyclohexanone, benzophenone or
acetophenone, an ester-based solvent such as ethyl acetate, butyl
acetate, ethylcellosolve acetate, methyl benzoate or phenyl
acetate, a polyhydric alcohol such as ethylene glycol,
ethyleneglycol monobutyl ether, ethyleneglycol monoethyl ether,
ethyleneglycol monomethyl ether, dimethoxyethane, propylene glycol,
diethoxymethane, triethyleneglycol monoethyl ether, glycerin or
1,2-hexanediol, or a derivative thereof, an alcohol-based solvent
such as methanol, ethanol, propanol, isopropanol or cyclohexanol, a
sulfoxide-based solvent such as dimethyl sulfoxide, or an
amide-based solvent such as N-methyl-2-pyrrolidone or
N,N-dimethylformamide. These solvents may be used alone or in
combinations of two or more.
[0158] Preferred among these, from the viewpoint of obtaining
favorable solubility of the polymer compound of the invention, and
the uniformity and viscosity characteristics for film formation,
include aromatic hydrocarbon-based solvents, ether-based solvents,
aliphatic hydrocarbon-based solvents, ester-based solvents and
ketone-based solvents, among which there are more preferred
toluene, xylene, ethylbenzene, diethylbenzene, trimethylbenzene,
n-propylbenzene, isopropylbenzene, n-butylbenzene, isobutylbenzene,
sec-butylbenzene, n-hexylbenzene, cyclohexylbenzene,
1-methylnaphthalene, tetralin, anisole, 4-methylanisole,
ethoxybenzene, cyclohexane, bicyclohexyl,
cyclohexenylcyclohexanone, n-heptylcyclohexane, n-hexylcyclohexane,
decalin, methyl benzoate, cyclohexanone, 2-propylcyclohexanone,
2-heptanone, 3-heptanone, 4-heptanone, 2-octanone, 2-nonanone,
2-decanone, dicyclohexylketone, acetophenone and benzophenone.
[0159] From the viewpoint of obtaining satisfactory film
formability and device characteristics, it is preferred to use a
combination of two or more solvents, it is more preferred to use
2-3 different solvents, and it is especially preferred to use 2
different solvents.
[0160] When two different solvents are included in the solution of
the invention, one of them may be in solid state at 25.degree. C.
From the viewpoint of obtaining favorable film formability, one of
the solvents preferably has a boiling point of 180.degree. C. or
higher and more preferably 200.degree. C. or higher. From the
viewpoint of obtaining favorable viscosity, the polymer compound
preferably dissolves in both solvents to a concentration of 1 wt %
or greater at 60.degree. C., and the polymer compound preferably
dissolves in one of the two solvents to a concentration of 1 wt %
or greater at 25.degree. C.
[0161] When two or more different solvents are present in the
solution of the invention, from the viewpoint of obtaining
favorable viscosity and film formability, the solvent with the
highest boiling point is preferably present at 40-90 wt %, more
preferably at 50-90 wt % and even more preferably at 65-85 wt % of
the total weight of solvents in the solution.
[0162] One or more different polymer compounds of the invention may
be in the solution of the invention, and a high molecular weight
compound other than the polymer compounds of the present invention
may be included in ranges that do not impair the device
characteristics.
[0163] The solution of the invention may also comprise water or a
metal or its salt, in a range of 1-1000 ppm by weight. Metals
include lithium, sodium, calcium, potassium, iron, copper, nickel,
aluminum, zinc, chromium, manganese, cobalt, platinum and iridium.
The solution of the invention may also contain silicon, phosphorus,
fluorine, chlorine, bromine or the like in ranges of 1-1000 ppm by
weight.
[0164] <Thin-Film>
The thin-film of the preferable embodiment comprises a polymer
compound of the invention, and it may be, for example, a
luminescent thin-film, conductive thin-film or organic
semiconductor thin-film.
[0165] The thin-film of the present embodiment may be formed, for
example, by spin coating, casting, microgravure coating, gravure
coating, bar coating, roll coating, wire bar coating, dip coating,
spray coating, screen printing, flexographic printing, offset
printing, ink jet printing, capillary coating or nozzle coating,
but it is preferably formed by screen printing, flexographic
printing, offset printing or ink jet printing, and more preferably
by an ink-jet method.
[0166] When a solution of the invention above is used to form the
thin-film, heating may be performed at a temperature of 100.degree.
C. or higher because of the high glass transition temperature of
the polymer compound of the invention in the solution, and it is
possible to minimize reduction in the device characteristics even
with heating at a temperature of 130.degree. C. Heating may even be
suitable at a temperature of 160.degree. C. or higher, depending on
the type of polymer compound.
[0167] A luminescent thin-film has a luminescent quantum yield of
preferably 30% or greater, more preferably 50% or greater, even
more preferably 60% or greater and most preferably 70% or greater,
from the viewpoint of obtaining satisfactory device luminance and
luminescence voltage.
[0168] For a conductive thin-film, the surface resistance is
preferably no greater than 1K .OMEGA./sq., more preferably no
greater than 100 .OMEGA./sq. and even more preferably no greater
than 10 .OMEGA./sq. The conductive thin-film may be doped with a
Lewis acid, ionic compound or the like, thereby further increasing
the electric conductivity.
[0169] The greater of the electron mobility or hole mobility of the
organic semiconductor thin-film is preferably 1.times.10.sup.-5
cm.sup.2/Vs or greater, more preferably 1.times.10.sup.-3
cm.sup.2/Vs or greater and even more preferably 1.times.10.sup.-5
cm.sup.2/Vs or greater. An organic transistor can be fabricated by
forming the organic semiconductor thin-film on a Si board
comprising a gate electrode and an insulating film made of
SiO.sub.2 or the like, and then forming a source electrode and
drain electrode of Au or the like.
[0170] <Light Emitting Device>
A light emitting device of the invention will now be described.
[0171] A light emitting device of the invention has electrodes
consisting of an anode and a cathode, and a layer comprising the
aforementioned polymer compound of the present invention formed
between the electrodes.
[0172] The layer comprising the polymer compound of the present
invention preferably consists of one or more luminescent layers,
hole transport layers, hole injection layers, electron transport
layers, electron injection layers or interlayers, more preferably
one or more electron transport layers, electron injection layers or
a luminescent layer, and even more preferably the layer is a
luminescent layer.
[0173] A luminescent layer is a layer having a luminescent
function. A hole transport layer is a layer having a hole
transporting function. An electron transport layer is a layer
having an electron transporting function. An interlayer is a layer
situated between the luminescent layer and anode and adjacent to
the luminescent layer, performing the role of separating the
luminescent layer and anode, or the luminescent layer and the hole
injection layer or hole transport layer. Electron transport layers
and hole transport layers are collectively referred to as "charge
transport layers", and electron injection layers and hole injection
layers are collectively referred to as "charge injection layers".
The luminescent layer, hole transport layer, hole injection layer,
electron transport layer, electron injection layer and interlayer
may each consist of a single layer or two or more layers.
[0174] When the layer comprising the polymer compound is a
luminescent layer, the luminescent layer may further comprise a
hole transport material, electron transport material, luminescent
material, and additives that extend the luminance lifetime of the
light emitting device. The term "luminescent material" as used
herein refers to a material exhibiting fluorescence and/or
phosphorescence (excluding polymer compounds of the invention).
[0175] When the layer comprising the polymer compound comprises
both the polymer compound of the invention and a hole transport
material, the proportion of the hole transport material with
respect to 100 parts by weight as the total of the polymer compound
of the invention and the hole transport material will normally be
1-80 parts by weight, and is preferably 5-60 parts by weight.
[0176] When the layer comprising the polymer compound comprises
both the polymer compound of the invention and an electron
transport material, the proportion of the electron transport
material with respect to 100 parts by weight as the total of the
polymer compound of the invention and the electron transport
material will normally be 1-80 parts by weight, and is preferably
5-60 parts by weight.
[0177] When the layer comprising the polymer compound comprises
both the polymer compound of the invention and a luminescent
material, the proportion of the luminescent material with respect
to 100 parts by weight as the total of the polymer compound of the
invention and the luminescent material will normally be 1-80 parts
by weight, and is preferably 5-60 parts by weight.
[0178] When the layer comprising the polymer compound comprises
both the polymer compound of the invention and two or more
materials selected from the group consisting of hole transport
materials, electron transport materials and luminescent materials,
the proportion of the luminescent material with respect to 100
parts by weight as the total will normally be 1-50 parts by weight
and preferably 5-40 parts by weight, and the total proportion of
the hole transport material and electron transport material with
respect to 100 parts by weight as the total will normally be 1-50
parts by weight and preferably 5-40 parts by weight.
[0179] The hole transport material, electron transport material and
luminescent material may also employ publicly known
low-molecular-weight compounds, triplet light emitting complexes
and high molecular weight compounds.
[0180] The aforementioned high molecular weight compounds include
polymers and copolymers (polymer and copolymer will be hereinafter
collectively referred to as "(co)polymers") having fluorenediyl
groups as constitutional units, (co)polymers having arylene groups
as constitutional units, (co)polymers having arylenevinylene groups
as constitutional units and (co)polymers having divalent aromatic
amine groups as constitutional units, which are described in
WO99/13692, WO99/48160, GB2340304A, WO00/53656, WO01/19834,
WO00/55927, GB2348316, WO00/46321, WO00/06665, WO99/54943,
WO99/54385, U.S. Pat. No. 5,777,070, WO98/06773, WO97/05184,
WO00/35987, WO00/53655, WO01/34722, WO99/24526, WO00/22027,
WO00/22026, WO98/27136, U.S. Pat. No. 573,636, WO98/21262, U.S.
Pat. No. 5,741,921, WO97/09394, WO96/29356, WO96/10617, EP0707020,
WO95/07955, Japanese Unexamined Patent Application Publication No.
2001-181618, Japanese Unexamined Patent Application Publication No.
2001-123156, Japanese Unexamined Patent Application Publication No.
2001-3045, Japanese Unexamined Patent Application Publication No.
2000-351967, Japanese Unexamined Patent Application Publication No.
2000-303066, Japanese Unexamined Patent Application Publication No.
2000-299189, Japanese Unexamined Patent Application Publication No.
2000-252065, Japanese Unexamined Patent Application Publication No.
2000-136379, Japanese Unexamined Patent Application Publication No.
2000-104057, Japanese Unexamined Patent Application Publication No.
2000-80167, Japanese Unexamined Patent Application Publication HEI
No. 10-324870, Japanese Unexamined Patent Application Publication
HEI No. 10-114891, Japanese Unexamined Patent Application
Publication HEI No. 9-111233 and Japanese Unexamined Patent
Application Publication HEI No. 9-45478.
[0181] The low-molecular-weight compounds include naphthalene
derivatives, anthracene and its derivatives, perylene and its
derivatives, polymethine-based, xanthene-based, coumarin-based and
cyanine-based pigments, metal complexes of 8-hydroxyquinoline and
its derivatives, aromatic amines, tetraphenylcyclopentadiene and
its derivatives and tetraphenylbutadiene and its derivatives, and
specifically they include the compounds described in Japanese
Unexamined Patent Application Publication SHO No. 57-51781 and
Japanese Unexamined Patent Application Publication SHO No.
59-194393.
[0182] Triplet light emitting complexes include Ir(ppy).sub.3,
Btp.sub.2Ir(acac), FIrpic, COM-1, COM-2, COM-3, and ADS066GE,
marketed by American Dye Source, Inc., which have iridium as the
central metal, PtOEP which has platinum as the central metal, and
Eu(TTA).sub.3-phen which has europium as the central metal. These
triplet light emitting complexes are indicated in the following
chemical formula, including those specifically described in Nature,
(1998), 395, 151, Appl. Phys. Lett. (1999), 75(1), 4, Proc.
SPIE-Int. Soc. Opt. Eng. (2001), 4105 (Organic Light-Emitting
Materials and Devices IV), 119, J. Am. Chem. Soc., (2001), 123,
4304, Appl. Phys. Lett., (1997), 71(18), 2596, Syn. Met., (1998),
94(1), 103, Syn. Met., (1999), 99(2), 1361, Adv. Mater., (1999),
11(10), 852 and Jpn. J. Appl. Phys., 34, 1883 (1995).
##STR00070## ##STR00071##
[0183] In addition, triplet light emitting complexes may be used by
conjugating them to main chain, side chain, end group of the
polymer compound of the present invention. Specific examples of
such a polymer compound include the polymer compound (PB-1) and
(PB-2) below.
##STR00072## ##STR00073##
[0184] The aforementioned additives include bipyridyls such as
2,2'-bipyridyl, 3,3'-bipyridyl and 4,4'-bipyridyl, and bipyridyl
derivatives such as 4-methyl-2,2'-bipyridyl,
5-methyl-2,2'-bipyridyl and 5,5'-dimethyl-2,2'-bipyridyl.
[0185] The optimum value for the thickness of the luminescent layer
will differ depending on the material used, and it may be selected
as the optimum value for driving voltage and luminous efficiency,
but for most cases it will be 1 nm-1 .mu.m, preferably 2 nm-500 nm,
more preferably 5 nm-200 nm and even more preferably 50 nm-150
nm.
[0186] The method of forming the luminescent layer may involve
formation of a film from a solution. Coating methods for forming
films from solutions include spin coating, casting, microgravure
coating, gravure coating, bar coating, roll coating, wire bar
coating, dip coating, spray coating, screen printing, flexographic
printing, offset printing, ink jet printing, capillary coating and
nozzle coating, but from the viewpoint of ease of pattern formation
and multicolor coating, printing methods such as screen printing,
flexographic printing, offset printing and ink jet printing are
preferred.
[0187] The solvent in the solution of the invention is preferably
one that can dissolve or evenly disperse the solid components in
the solution. The solvent may be a chlorine-based solvent such as
chloroform, methylene chloride, 1,2-dichloroethane,
1,1,2-trichloroethane, chlorobenzene or o-dichlorobenzene, an
ether-based solvent such as tetrahydrofuran, dioxane, an aromatic
hydrocarbon-based solvent such as toluene, xylene, mesitylene,
ethylbenzene, n-hexylbenzene, cyclohexylbenzene, anisole, or
4-methylanisole, an aliphatic hydrocarbon-based solvent such as
cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptane,
n-octane, n-nonane or n-decane, a ketone-based solvent such as
acetone, methyl ethyl ketone, or cyclohexanone, an ester-based
solvent such as ethyl acetate, butyl acetate, or ethylcellosolve
acetate, a polyhydric alcohol such as ethylene glycol,
ethyleneglycol monobutyl ether, ethyleneglycol monoethyl ether,
ethyleneglycol monomethyl ether, dimethoxyethane, propylene glycol,
diethoxymethane, triethyleneglycol monoethyl ether, glycerin or
1,2-hexanediol, or a derivative thereof, an alcohol-based solvent
such as methanol, ethanol, propanol, isopropanol or cyclohexanol, a
sulfoxide-based solvent such as dimethyl sulfoxide, or an
amide-based solvent such as N-methyl-2-pyrrolidone or
N,N-dimethylformamide. These solvents may be used alone or in
combinations of two or more.
[0188] The light emitting device of the invention may be a light
emitting device having an electron transport layer formed between a
cathode and a luminescent layer, a light emitting device having a
hole transport layer formed between an anode and a luminescent
layer, or a light emitting device having an electron transport
layer formed between a cathode and a luminescent layer and having a
hole transport layer formed between an anode and a luminescent
layer.
[0189] Examples of such light emitting device structures include
the following structures a) to d).
a) Anode/luminescent layer/cathode b) Anode/hole transport
layer/luminescent layer/cathode c) Anode/luminescent layer/electron
transport layer/cathode d) Anode/hole transport layer/luminescent
layer/electron transport layer/cathode (Here, the "/" indicates
that the layers are laminated adjacent to each other; same
hereunder.)
[0190] In each of these structures, an interlayer may be provided
between the luminescent layer and anode, adjacent to the
luminescent layer. Examples of such light emitting device
structures include the following structures a') to d').
a') Anode/interlayer/luminescent layer/cathode b') Anode/hole
transport layer/interlayer/luminescent layer/cathode c')
Anode/interlayer/luminescent layer/electron transport layer/cathode
d') Anode/hole transport layer/interlayer/luminescent
layer/electron transport layer/cathode
[0191] When the light emitting device of the invention has a hole
transport layer, the hole transport layer will usually contain the
hole transport material (high molecular weight compound or
low-molecular-weight compound). Examples of hole transport
materials include polyvinylcarbazole and its derivatives,
polysilane and its derivatives, polysiloxane derivatives having
aromatic amines on side chains or the main chain, pyrazoline
derivatives, arylamine derivatives, stilbene derivatives,
triphenyldiamine derivatives, polyaniline and its derivatives,
polythiophene and its derivatives, polypyrrole and its derivatives,
poly(p-phenylenevinylene) and its derivatives and
poly(2,5-thienylenevinylene) and its derivatives, as well as those
described in Japanese Unexamined Patent Application Publication SHO
No. 63-70257 and 63-175860 and Japanese Unexamined Patent
Application Publication HEI No. 2-135359, 2-135361, 2-209988,
3-37992 and 3-152184.
[0192] Preferred among these as high molecular weight compounds are
polyvinylcarbazole and its derivatives, polysilane and its
derivatives, polysiloxane derivatives having aromatic amine
compounds on side chains or the main chain, polyaniline and its
derivatives, polythiophene and its derivatives,
poly(p-phenylenevinylene) and its derivatives and
poly(2,5-thienylenevinylene) and its derivatives, and
polyvinylcarbazole and its derivatives, polysilane and its
derivatives and polysiloxane derivatives having aromatic amines on
side chains or the main chain are more preferred.
[0193] Pyrazoline derivatives, arylamine derivatives, stilbene
derivatives and triphenyldiamine derivatives are preferred among
these as low-molecular-weight compounds. These low-molecular-weight
compounds are preferably used after dispersion in a high molecular
binder.
[0194] The high molecular binder is preferably a compound that does
not excessively hinder charge transport and has low absorption of
visible light, and examples thereof include poly(N-vinylcarbazole),
polyaniline and its derivatives, polythiophene and its derivatives,
poly(p-phenylenevinylene) and its derivatives,
poly(2,5-thienylenevinylene) and its derivatives, polycarbonates,
polyacrylates, polymethyl acrylates, polymethyl methacrylates,
polystyrenes, polyvinyl chlorides and polysiloxanes.
[0195] Polyvinylcarbazole and its derivatives may be obtained, for
example, by cationic polymerization or radical polymerization from
vinyl monomers.
[0196] Examples of polysilane and its derivatives include the
compounds mentioned in Chem. Rev. Vol. 89, p. 1359 (1989) and
GB2300196. The synthesis methods described in this literature may
be used, although the Kipping method is preferred.
[0197] Because the skeletal structure of siloxane has essentially
no hole transport property, polysiloxane and its derivatives are
preferably compounds having a structure with the aforementioned
low-molecular-weight hole transport material on a side chain or the
main chain, and more preferably compounds having a hole
transporting aromatic amine on a side chain or the main chain.
[0198] The method of forming the hole transport layer may be film
formation from a mixture with a high molecular binder, if a
low-molecular-weight compound is used, or film formation from a
solution, if a high molecular weight compound is used.
[0199] The solvent used for film formation from a solution is
preferably one that can dissolve or evenly disperse the hole
transport material. The solvent may be a chlorine-based solvent
such as chloroform, methylene chloride, 1,2-dichloroethane,
1,1,2-trichloroethane, chlorobenzene or o-dichlorobenzene, an
ether-based solvent such as tetrahydrofuran or dioxane, an aromatic
hydrocarbon-based solvent such as toluene, xylene, mesitylene,
ethylbenzene, hexylbenzen, n-hexylbenzene, cyclohexylbenzene,
anisole, or 4-methylanisole, an aliphatic hydrocarbon-based solvent
such as cyclohexane, methylcyclohexane, n-pentane, n-hexane,
n-heptane, n-octane, n-nonane or n-decane, a ketone-based solvent
such as acetone, methyl ethyl ketone or cyclohexanone, an
ester-based solvent such as ethyl acetate, butyl acetate or
ethylcellosolve acetate, a polyhydric alcohol such as ethylene
glycol, ethyleneglycol monobutyl ether, ethyleneglycol monoethyl
ether, ethyleneglycol monomethyl ether, dimethoxyethane, propylene
glycol, diethoxymethane, triethyleneglycol monoethyl ether,
glycerin or 1,2-hexanediol, or a derivative thereof, an
alcohol-based solvent such as methanol, ethanol, propanol,
isopropanol or cyclohexanol, a sulfoxide-based solvent such as
dimethyl sulfoxide, or an amide-based solvent such as
N-methyl-2-pyrrolidone or N,N-dimethylformamide. These solvents may
be used alone or in combinations of two or more.
[0200] The film formation from a solution may be accomplished by a
coating method such as spin coating, casting, microgravure coating,
gravure coating, bar coating, roll coating, wire bar coating, dip
coating, spray coating, screen printing, flexographic printing,
offset printing, ink jet printing, capillary coating or nozzle
coating.
[0201] The optimum value for the film thickness of the hole
transport layer will differ depending on the material used, and it
may be selected so that the driving voltage and luminous efficiency
are suitable values, but the thickness must be sufficient to avoid
generation of pinholes, while an excessive thickness is not
preferred as it may increase the driving voltage of the device. The
film thickness of the hole transport layer is therefore usually 1
nm-1 .mu.m, preferably 2-500 nm and more preferably 5-200 nm.
[0202] When the light emitting device of the invention has an
electron transport layer, the electron transport layer will usually
contain the electron transport material (high molecular weight
compound or low-molecular-weight compound). Known electron
transport materials may be used, examples of which include
oxadiazole derivatives, anthraquinodimethane and its derivatives,
benzoquinone and its derivatives, naphthoquinone and its
derivatives, anthraquinone and its derivatives,
tetracyanoquinodimethane and its derivatives, fluorenone
derivatives, diphenyldicyanoethylene and its derivatives,
diphenoquinone derivatives, metal complexes of 8-hydroxyquinoline
and its derivatives, polyquinoline and its derivatives,
polyquinoxaline and its derivatives and polyfluorene and its
derivatives, as well as the compounds described in Japanese
Unexamined Patent Application Publication SHO No. 63-70257,
Japanese Unexamined Patent Application Publication SHO No.
63-175860, Japanese Unexamined Patent Application Publication HEI
No. 2-135359, Japanese Unexamined Patent Application Publication
HEI No. 2-135361, Japanese Unexamined Patent Application
Publication HEI No. 2-209988, Japanese Unexamined Patent
Application Publication HEI No. 3-37992 and Japanese Unexamined
Patent Application Publication HEI No. 3-152184, among which
oxadiazole derivatives, benzoquinone and its derivatives,
anthraquinone and its derivatives, metal complexes of
8-hydroxyquinoline and its derivatives, polyquinoline and its
derivatives, polyquinoxaline and its derivatives and polyfluorene
and its derivatives are preferred, and
2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole,
benzoquinone, anthraquinone, tris(8-quinolinol)aluminum and
polyquinoline are even more preferred.
[0203] The method of forming the electron transport layer may be
vacuum vapor deposition from a powder or film formation from a
solution or molten state, if a low-molecular-weight compound is
used, or film formation from a solution or molten state, if a high
molecular weight compound is used. The aforementioned high
molecular binder may also be used for film formation from a
solution or molten state.
[0204] The solvent used for film formation from a solution is
preferably a solvent that can dissolve or evenly disperse the
electron transport material and/or high molecular binder. The
solvent may be a chlorine-based solvent such as chloroform,
methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane,
chlorobenzene or o-dichlorobenzene, an ether-based solvent such as
tetrahydrofuran or dioxane, an aromatic hydrocarbon-based solvent
such as toluene, xylene, mesitylene, ethylbenzene, hexylbenzen,
n-hexylbenzene, cyclohexylbenzene, anisole, or 4-methylanisole, an
aliphatic hydrocarbon-based solvent such as cyclohexane,
methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane,
n-nonane or n-decane, a ketone-based solvent such as acetone,
methyl ethyl ketone or cyclohexanone, an ester-based solvent such
as ethyl acetate, butyl acetate or ethylcellosolve acetate, a
polyhydric alcohol such as ethylene glycol, ethyleneglycol
monobutyl ether, ethyleneglycol monoethyl ether, ethyleneglycol
monomethyl ether, dimethoxyethane, propylene glycol,
diethoxymethane, triethyleneglycol monoethyl ether, glycerin or
1,2-hexanediol, or a derivative thereof, an alcohol-based solvent
such as methanol, ethanol, propanol, isopropanol or cyclohexanol, a
sulfoxide-based solvent such as dimethyl sulfoxide, or an
amide-based solvent such as N-methyl-2-pyrrolidone or
N,N-dimethylformamide. These solvents may be used alone or in
combinations of two or more.
[0205] The film formation from a solution or molten state may be
accomplished by a coating method such as spin coating, casting,
microgravure coating, gravure coating, bar coating, roll coating,
wire bar coating, dip coating, spray coating, screen printing,
flexographic printing, offset printing, ink jet printing, capillary
coating or nozzle coating.
[0206] The optimum value for the film thickness of the electron
transport layer will differ depending on the material used, and it
may be selected so that the driving voltage and luminous efficiency
are suitable values, but the thickness must be sufficient to avoid
generation of pinholes, while an excessive thickness is not
preferred as it may increase the driving voltage of the device. The
film thickness of the electron transport layer is therefore usually
1 nm-1 .mu.m, preferably 2-500 nm and more preferably 5-200 nm.
[0207] The hole injection layer and electron injection layer, of
the charge transport layers formed adjacent to the electrodes, have
the function of improving the charge injection efficiency from the
electrodes, and have an effect of lowering the driving voltage of
the light emitting device.
[0208] In order to increase adhesiveness with and improve charge
injection from the electrodes, there may be provided adjacent to
the electrodes a charge injection layer or insulating layer
(normally with a mean film thickness of 0.5-4.0 nm, same
hereunder), while a thin buffer layer may be inserted at the
interface with the charge transport layer or luminescent layer to
improve the interfacial adhesiveness and prevent intermixture.
[0209] The order and number of the laminated layers and the
thickness of each layer may be modified in consideration of the
desired luminous efficiency and device life.
[0210] According to the invention, light emitting devices provided
with charge injection layers include light emitting devices
provided with a charge injection layer adjacent to the cathode and
light emitting devices provided with a charge injection layer
adjacent to the anode. Examples of such light emitting device
structures include the following structures e) to p).
e) Anode/charge injection layer/luminescent layer/cathode f)
Anode/luminescent layer/charge injection layer/cathode g)
Anode/charge injection layer/luminescent layer/charge injection
layer/cathode h) Anode/charge injection layer/hole transport
layer/luminescent layer/cathode i) Anode/hole transport
layer/luminescent layer/charge injection layer/cathode j)
Anode/charge injection layer/hole transport layer/luminescent
layer/charge injection layer/cathode k) Anode/charge injection
layer/luminescent layer/electron transport layer/cathode l)
Anode/luminescent layer/electron transport layer/charge injection
layer/cathode m) Anode/charge injection layer/luminescent
layer/electron transport layer/charge injection layer/cathode n)
Anode/charge injection layer/hole transport layer/luminescent
layer/electron transport layer/cathode o) Anode/hole transport
layer/luminescent layer/electron transport layer/charge injection
layer/cathode p) Anode/charge injection layer/hole transport
layer/luminescent layer/electron transport layer/charge injection
layer/cathode
[0211] In each of these structures, an interlayer may be provided
between the luminescent layer and anode, adjacent to the
luminescent layer. In this case, the interlayer may even serve as
the hole injection layer and/or the hole transport layer.
[0212] The charge injection layer may be a layer comprising a
conductive polymer, a layer provided between the anode and hole
transport layer which comprises a material having an ionization
potential between that of the anode material and the hole transport
material in the hole transport layer, or a layer provided between
the cathode and electron transport layer which comprises a material
having an electron affinity between that of the cathode material
and the electron transport material in the electron transport
layer.
[0213] When the charge injection layer is a layer comprising a
conductive polymer, the electric conductivity of the conductive
polymer is preferably 1.times.10.sup.-5-1.times.10.sup.3 S/cm, and
in order to reduce the leak current between luminescent picture
devices, it is more preferably 1.times.10.sup.-5-1.times.10.sup.2
S/cm and even more preferably 1.times.10.sup.-5-1.times.10.sup.1
S/cm. In order for the electric conductivity of the conductive
polymer to be within this range, the conductive polymer will
usually be moderately doped with an ion.
[0214] The type of ion used for doping may be an anion for the hole
injection layer or a cation for the electron injection layer.
Examples of anions include polystyrenesulfonate ion,
alkylbenzenesulfonate ion and camphorsulfonate ion, and examples of
cations include lithium ion, sodium ion, potassium ion and
tetrabutylammonium ion.
[0215] The material used for the charge injection layer may be
selected in consideration of the relationship between the electrode
and the material in the adjacent layer, and examples include
conductive polymers, such as polyaniline and its derivatives,
polythiophene and its derivatives, polypyrrole and its derivatives,
polyphenylenevinylene and its derivatives, polythienylenevinylene
and its derivatives, polyquinoline and its derivatives and
polyquinoxaline and its derivatives, polymers comprising an
aromatic amine structure on the main chain or a side chain, or
metal phthalocyanines (copper phthalocyanine or the like), and
carbon.
[0216] The material of the insulating layer may be a metal
fluoride, metal oxide, organic insulating material, or the like.
The light emitting device provided with the insulating layer may be
a light emitting device with the insulating layer adjacent to the
cathode or a light emitting device with the insulating layer
adjacent to the anode.
[0217] Examples of such light emitting device structures include
the following structures q) to ab).
q) Anode/insulating layer/luminescent layer/cathode r)
Anode/luminescent layer/insulating layer/cathode s)
Anode/insulating layer/luminescent layer/insulating layer/cathode
t) Anode/insulating layer/hole transport layer/luminescent
layer/cathode u) Anode/hole transport layer/luminescent
layer/insulating layer/cathode v) Anode/insulating layer/hole
transport layer/luminescent layer/insulating layer/cathode w)
Anode/insulating layer/luminescent layer/electron transport
layer/cathode x) Anode/luminescent layer/electron transport
layer/insulating layer/cathode y) Anode/insulating
layer/luminescent layer/electron transport layer/insulating
layer/cathode z) Anode/insulating layer/hole transport
layer/luminescent layer/electron transport layer/cathode aa)
Anode/hole transport layer/luminescent layer/electron transport
layer/insulating layer/cathode ab) Anode/insulating layer/hole
transport layer/luminescent layer/electron transport
layer/insulating layer/cathode
[0218] In each of these structures, an interlayer may be provided
between the luminescent layer and anode, adjacent to the
luminescent layer. In this case, the interlayer may even serve as
the hole injection layer and/or the hole transport layer.
[0219] Structures employing interlayers in structures a) to ab)
preferably have, as an interlayer provided between the anode and
luminescent layer, a material with ionization potential, between
the anode or the hole injection layer or hole transport layer, and
the polymer compound composing the luminescent layer.
[0220] The material used in the interlayer may be a
polyvinylcarbazole or a derivative thereof, a polyarylene
derivative having an aromatic amine on a side chain or the main
chain, or a polymer comprising an aromatic amine such as an
arylamine derivative or triphenyldiamine derivative.
[0221] When a high molecular weight material is used, the
film-forming method for the interlayer may be a method of formation
from a solution.
[0222] The solvent used for film formation from a solution is
preferably one that can dissolve or evenly disperse the material to
be used in the interlayer. The solvent may be a chlorine-based
solvent such as chloroform, methylene chloride, 1,2-dichloroethane,
1,1,2-trichloroethane, chlorobenzene or o-dichlorobenzene, an
ether-based solvent such as tetrahydrofuran or dioxane, an aromatic
hydrocarbon-based solvent such as toluene, xylene, mesitylene,
ethylbenzene, hexylbenzen, n-hexylbenzene, cyclohexylbenzene,
anisole or 4-methylanisole, an aliphatic hydrocarbon-based solvent
such as cyclohexane, methylcyclohexane, n-pentane, n-hexane,
n-heptane, n-octane, n-nonane or n-decane, a ketone-based solvent
such as acetone, methyl ethyl ketone or cyclohexanone, an
ester-based solvent such as ethyl acetate, butyl acetate or
ethylcellosolve acetate, a polyhydric alcohol such as ethylene
glycol, ethyleneglycol monobutyl ether, ethyleneglycol monoethyl
ether, ethyleneglycol monomethyl ether, dimethoxyethane, propylene
glycol, diethoxymethane, triethyleneglycol monoethyl ether,
glycerin or 1,2-hexanediol, or a derivative thereof, an
alcohol-based solvent such as methanol, ethanol, propanol,
isopropanol or cyclohexanol, a sulfoxide-based solvent such as
dimethyl sulfoxide, or an amide-based solvent such as
N-methyl-2-pyrrolidone or N,N-dimethylformamide. These solvents may
be used alone or in combinations of two or more.
[0223] The film formation from a solution may be accomplished by a
coating method such as spin coating, casting, microgravure coating,
gravure coating, bar coating, roll coating, wire bar coating, dip
coating, spray coating, screen printing, flexographic printing,
offset printing, ink jet printing, capillary coating or nozzle
coating.
[0224] The optimum value for the film thickness of the interlayer
will differ depending on the material used, and it may be selected
as the optimum value for driving voltage and luminous efficiency,
but for most cases it will be 1 nm-1 .mu.m, preferably 2-500 nm and
more preferably 5-200 nm.
[0225] When an interlayer is provided adjacent to the luminescent
layer, and especially when both layers are formed by a coating
method, the materials of the two layers sometimes become mixed,
having undesirable effects on the device characteristics. When the
luminescent layer is formed by a coating method after the
interlayer has been formed by coating, mixing between the materials
of the two layers can be reduced by a method of forming the
interlayer by coating and heating the interlayer to insolubilize it
to the organic solvent used to form the luminescent layer, and then
subsequently forming the luminescent layer. The heating temperature
will normally be 150-300.degree. C. The heating time will usually
be 1 minute-1 hour. In this case, the heating may be followed by
rinsing the interlayer with the solvent used to form the
luminescent layer, before forming the luminescent layer, in order
to remove the components that have not been insolubilized to the
solvent by heating. Such rinsing may be omitted if the
insolubilization by heating has been sufficient. In order to
achieve sufficient insolubilization by heating, it is preferred to
use a compound having a polymerizable group in the molecule, as the
high molecular weight compound to be used in the interlayer. The
number of polymerizable groups is preferably at least 5% of the
number of constitutional units in the molecule.
[0226] The substrate for a light emitting device of the invention
need only be one that does not undergo alteration during formation
of the electrodes and formation of the organic material layers, and
it may be composed of a material such as glass, plastic, a polymer
film or silicon. In the case of an opaque substrate, the opposite
electrode is preferably transparent or semi-transparent.
[0227] Either or both the anode and cathode in a light emitting
device of the invention will usually be transparent or
semi-transparent, but preferably the anode is transparent or
semi-transparent.
[0228] The material for the anode may be a conductive metal oxide
film, semi-transparent metal thin-film or the like, and
specifically a film formed using a conductive compound such as
indium oxide, zinc oxide, tin oxide or their complexes such as
indium tin oxide (ITO) and indium zinc oxide, or alternatively NESA
and the like, or gold, platinum, silver or copper, among which ITO,
indium zinc oxide and tin oxide are preferred. The forming method
may be vacuum vapor deposition, sputtering, ion plating, plating or
the like. The anode used may be an organic transparent conductive
film made of polyaniline or its derivative or polythiophene or its
derivative. The anode may even consist of two or more built-up
structures.
[0229] The film thickness of the anode may be selected in
consideration of light permeability and electric conductivity, and
for example, it may be 10 nm-10 .mu.m, preferably 20 nm-1 .mu.m and
more preferably 50-500 nm.
[0230] In order to facilitate charge injection, there may be
provided on the anode a layer composed of a phthalocyanine
derivative, conductive polymer, carbon or the like, or an
insulating layer composed of a metal oxide, metal fluoride, organic
insulating material or the like.
[0231] The material for the cathode is preferably one with a low
work function, e.g. a metal such as lithium, sodium, potassium,
rubidium, cesium, beryllium, magnesium, calcium, strontium, barium,
aluminum, scandium, vanadium, zinc, yttrium, indium, cerium,
samarium, europium, terbium or ytterbium, or an alloy of two or
more of these metals, or an alloy of one or more of these metals
with one or more of gold, silver, platinum, copper, manganese,
titanium, cobalt, nickel, tungsten or tin, or graphite or a
graphite interlaminar compound. Examples of alloys include
magnesium-silver alloys, magnesium-indium alloys,
magnesium-aluminum alloys, indium-silver alloys, lithium-aluminum
alloys, lithium-magnesium alloys, lithium-indium alloys and
calcium-aluminum alloys. The cathode may also consist of two or
more built-up structures.
[0232] The film thickness of the cathode may be modified in
consideration of electric conductivity and durability, and it will
usually be 10 nm-10 .mu.m, preferably 20 nm-1 .mu.m and more
preferably 50-500 nm.
[0233] The method used to form the cathode may be vacuum vapor
deposition, sputtering, or a laminating method involving
thermocompression bonding of a metal thin-film. Also, between the
cathode and organic layer (that is, any layer comprising a polymer
compound of the invention) there may be provided a layer composed
of a conductive polymer, or a layer with a mean film thickness of
no greater than 2 nm composed of a metal oxide, metal fluoride or
organic insulating material, and a protective layer for protection
of the light emitting device may also be placed after formation of
the cathode. For prolonged stable use of the light emitting device,
a protective layer and/or protective cover is preferably situated
to protect the device from the external environment.
[0234] Such a protective layer may be a high molecular weight
compound, metal oxide, metal fluoride or metal boride. The
protective cover may be a metal sheet, glass plate, or a plastic
sheet that has been subjected to low-permeability treatment on the
surface, and the protective cover may be hermetically attached to
the device board with a thermosetting resin or photocuring resin. A
spacer may be used to maintain spacing, thus helping to prevent
damage to the device. By filling an inert gas such as nitrogen or
argon into the spacing, it is possible to prevent oxidation of the
cathode, and setting a desiccant such as barium oxide in the space
will help to prevent damage to the device by moisture adsorbed in
the production steps or trace moisture infiltrating through the
cured resin. It is preferred to employ one or more of these
strategies.
[0235] FIG. 1 is a schematic cross-sectional view of an embodiment
of the light emitting device of the invention (the light emitting
device having the structure p)). The light emitting device 100
shown in FIG. 1 comprises a substrate 10, and comprises an anode
11, a charge injection layer 12, a hole transport layer 13, a
luminescent layer 14, an electron transport layer 15, a charge
injection layer 16 and a cathode 17 formed on the substrate 10. The
anode 11 is provided in contact with the substrate 10. The charge
injection layer 12, the hole transport layer 13, the luminescent
layer 14, the electron transport layer 15, the charge injection
layer 16 and the cathode 17 are laminated onto the side of the
anode 11 opposite the substrate 10, in that order.
[0236] FIG. 2 is a schematic cross-sectional view of other
embodiment of the light emitting device of the invention (the light
emitting device having the structure h)). The light emitting device
110 shown in FIG. 2 comprises a substrate 10, and comprises an
anode 11, a charge injection layer 12, a hole transport layer 13, a
luminescent layer 14 and a cathode 17 formed on the substrate 10.
The anode 11 is provided in contact with the substrate 10. The
charge injection layer 12, the hole transport layer 13, the
luminescent layer 14 and the cathode 17 are laminated onto the side
of the anode 11 opposite the substrate 10, in that order.
[0237] The light emitting device of the invention is useful as a
planar light source, segment display device, dot matrix display
device or liquid crystal display apparatus backlight.
[0238] A planar anode and cathode may be stacked together in order
to obtain planar luminescence using the light emitting device of
the invention. Luminescence in a pattern can be obtained by a
method in which a mask with a patterned window is set on the front
side of the planar light emitting device, a method in which layers
for non-luminous sections are formed extremely thin to render them
essentially non-luminous, and a method in which an anode or
cathode, or both electrodes, are formed in a pattern shape. By
forming a pattern by any of these methods, and configuring some
electrodes to be independently ON/OFF switchable, it is possible to
obtain a segment type display device allowing display of numerals,
letters or simple symbols. For a dot matrix display device, the
anode and cathode may both be formed as stripes and configured in a
crossing manner. A partial color display or multicolor display can
also be formed by a method in which different types of polymer
fluorescent materials with different luminescent colors are coated
or a method using a color filter or fluorescence conversion filter.
The dot matrix display device may be passively driven or actively
driven in combination with a TFT or the like. These display devices
may be used as display devices for computers, televisions, portable
terminals, cellular phones, car navigation systems, video camera
viewfinders, and the like.
[0239] The planar light emitting device is a selfluminous thin
type, and can therefore also be suitably used as a backlight planar
light source for a liquid crystal display apparatus, or a planar
illumination light source. Moreover, using a flexible substrate
will allow its use as a curved light source or display device.
[0240] FIG. 3 is a schematic cross-sectional view of an embodiment
of the planar light source of the invention. The planar light
source 200 shown in FIG. 3 comprises a substrate 20, an anode 21, a
charge injection layer 22, a luminescent layer 23, a cathode 24 and
a protective layer 25. The anode 21 is provided in contact with the
substrate 20. The charge injection layer 22, the luminescent layer
23 and the cathode 24 are laminated onto the side of the anode 21
opposite the substrate 20, in that order. In addition, the
protective layer 25 is formed so as to cover the anode 21, the
charge injection layer 22, the luminescent layer 23 and the cathode
24 that are formed on the substrate 20, and to contact with
substrate 20 at the end part. Luminescent layer 23 comprises the
above polymer compound.
[0241] In addition, the planer light source 200 shown in FIG. 3
further comprises luminescent layers other than the luminescent
layer 23 and is capable of becoming a color display device by using
red luminescence material, blue luminescence material, and green
luminescence material in each luminescent layer and controlling the
drive of each luminescent layer.
EXAMPLES
[0242] The present invention will now be explained in greater
detail by examples.
[0243] (Method for Determining the Number-Average Molecular Weights
and Weight-Average Molecular Weights)
Throughout the examples, the polystyrene equivalent number-average
molecular weights and polystyrene equivalent weight-average
molecular weights were determined by gel permeation chromatography
(GPC, trade name: LC-10Avp by Shimadzu Corp.). The polymer compound
to be measured was dissolved in tetrahydrofuran to a concentration
of about 0.5 wt % and 30 .mu.L thereof was injected into the GPC.
The GPC mobile phase was tetrahydrofuran, and the flow rate was 0.6
mL/min. The columns used were two TSKgel SuperHM-H (Tosoh Corp.)
columns and one TSKgel SuperH2000 (Tosoh Corp.) column, connected
in series. The detector used was a differential refractometer
(trade name: RID-10A, product of Shimadzu Corp.).
Synthesis Example 1
Synthesis of Compound 1
[0244] After nitrogen-exchange of a 5 L three-necked flask,
1-bromo-3-n-hexylbenzene (226 g) was measured out and dissolved in
2.5 L of dehydrated tetrahydrofuran. The obtained solution was
cooled to below -75.degree. C., a 2.5 M n-butyllithium/n-hexane
solution (358 ml) was added dropwise and the mixture was stirred
for 5 hours while keeping the temperature below -75.degree. C. A
solution of 150 g of 2-methoxycarbonyl-4,4'-dibromobiphenyl
dissolved in 400 ml of dehydrated tetrahydrofuran was added
dropwise to the obtained solution while keeping the temperature
below -70.degree. C. The compound
2-methoxycarbonyl-4,4'-dibromobiphenyl was synthesized by the
method described in Journal of the American Chemical Society
(1956), 78, 3196-3198.
[0245] The temperature of the obtained solution was slowly raised
to room temperature, and it was stirred overnight. The reaction
mixture was then stirred at 0.degree. C. while adding 150 ml of
water dropwise. After distilling off the solvent, 200 ml of water
was added to the residue and extraction was performed once with 1 L
of hexane and twice with 100 ml of hexane. The organic layers were
combined and rinsed with 200 ml of brine, the aqueous layer was
extracted again with 100 ml of hexane, and the obtained organic
layer was dried over magnesium sulfate. The solvent was distilled
off to obtain 264 g of a crude product of compound 1 represented by
the following formula. This was used in the following step without
purification.
##STR00074##
Synthesis Example 2
Synthesis of Compound 2
[0246] After measuring out 264 g of compound 1 synthesized in
Synthesis Example 1 into a three-necked flask, it was dissolved in
900 ml of dichloromethane and exchanged with nitrogen. The obtained
solution was cooled to below 0.degree. C., and 245 ml of a boron
trifluoride/diethyl ether complex was added dropwise while keeping
the temperature below 5.degree. C. The temperature was slowly
raised to room temperature, and the solution was stirred overnight.
The reaction mixture was poured into 2 L of ice water while
stirring, and stirring was continued for 30 minutes. The obtained
solution was separated and the aqueous layer was extracted with 100
ml of dichloromethane. The organic layers were combined, and 1 L of
a 10 wt % potassium phosphate aqueous solution was added for
separation, after which the organic layer was washed twice with 1 L
of water. After drying the organic layer over magnesium sulfate,
the solvent was distilled off and the obtained oil was dissolved in
200 ml of toluene, and then passed through a silica gel-covered
glass filter for filtering. The solvent was distilled off, and then
500 ml of methanol was added and the mixture was vigorously
stirred. The obtained crystals were filtered and washed with
methanol. Recrystallization was performed with a hexane/butyl
acetate mixed solvent to obtain 121 g of compound 2 represented by
the following formula.
##STR00075##
[0247] .sup.1H-NMR (300 MH.sub.Z, CDCl.sub.3); .delta.0.86 (6H, t),
1.26 (12H, m), 1.52 (4H, m), 2.51 (4H, t), 6.87 (2H, d), 7.00 (2H,
s), 7.04 (2H, d), 7.12 (2H, t), 7.46 (2H, dd), 7.48 (2H, d), 7.55
(2H, d) ppm.
Synthesis Example 3
Synthesis of Compound 3
[0248] After measuring out 50 g of compound 2 into a three-necked
flask, it was exchanged with nitrogen. Next, 500 ml of dehydrated
tetrahydrofuran was added and the mixture was cooled to below
-70.degree. C. The obtained solution was cooled to below
-70.degree. C. while adding dropwise 68 ml of a 2.5 M
n-butyllithium/n-hexane solution. After the dropwise addition, the
mixture was stirred for 4 hours while maintaining that temperature.
After then adding 44 ml of
2-isopropyloxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, the mixture
was slowly raised to room temperature and stirred overnight. The
reaction mixture was cooled to -30.degree. C., and then 78 ml of a
2 M hydrochloric acid/diethyl ether solution was added dropwise
prior to raising to room temperature. After distilling off the
solvent, 400 ml of toluene was added for dissolution, the mixture
was passed through a silica gel-covered glass filter for
filtration, and the solvent of the obtained solution was distilled
off to obtain 50 g of a crude product. Recrystallization was
performed from a toluene/acetonitrile solvent under a nitrogen
atmosphere, to obtain 34 g of compound 3 represented by the
following formula.
##STR00076##
[0249] .sup.1H-NMR (300 MH.sub.Z, CDCl.sub.3); .delta.0.86 (6H, t),
1.26-1.29 (12H, m), 1.31 (24H, s), 1.52-1.53 (4H, m), 2.50 (4H, t),
6.92 (2H, d), 7.00 (2H, d), 7.08 (2H, t), 7.13 (2H, s), 7.77 (2H,
d), 7.81-7.82 (4H, m) ppm.
Comparative Example 1
Synthesis of Polymer Compound 1
[0250] After combining compound 4 (3.1502 g, 5.94 mmol) represented
by the following formula:
##STR00077##
compound 5 (2.9615 g, 5.40 mmol) represented by the following
formula:
##STR00078##
compound 6 (0.4431 g, 0.60 mmol) represented by the following
formula:
##STR00079##
dichlorobis(triphenylphosphine)palladium (4.3 mg),
trioctylmethylammonium chloride (trade name: Aliquat 336 (product
of Aldrich Co.), 0.79 g) and toluene (60 ml) under an inert
atmosphere, the mixture was heated to 105.degree. C.
[0251] To the reaction mixture there was added dropwise a 2 M
Na.sub.2CO.sub.3 aqueous solution (16.3 ml), and it was circulated
for 3 hours and 10 minutes. After the reaction, phenylboric acid
(73 mg), dichlorobis(triphenylphosphine)palladium (4.1 mg) and
toluene (60 mL) were added and circulation was continued for 15.5
hours. Next, a sodium N,N-diethyldithiocarbamate aqueous solution
was added and the mixture was stirred at 80.degree. C. for 2 hours.
After cooling, the organic layer was washed twice with water (78
ml), twice with a 3 wt % acetic acid aqueous solution (78 ml) and
twice with water (78 ml), and the obtained solution was added
dropwise to methanol (1500 mL) and filtered to obtain a
precipitate.
[0252] The precipitate was dissolved in toluene (190 mL) and passed
through an alumina column and a silica gel column in that order for
purification. The obtained solution was added dropwise to methanol
(930 ml) and stirred, and then the resulting precipitate was
filtered and dried to obtain 3.61 g of polymer compound 1. The
polystyrene equivalent number-average molecular weight of polymer
compound 1 was 1.0.times.10.sup.5, and the polystyrene equivalent
weight-average molecular weight was 2.3.times.10.sup.5.
[0253] Polymer compound 1 is a random copolymer comprising a
constitutional unit represented by the following formula (1a):
##STR00080##
and a constitutional unit represented by the following formula
(1b):
##STR00081##
in a molar ratio of 95:5, as the theoretical value calculated from
the charged starting materials.
Example 1
Synthesis of Polymer Compound 2
[0254] After combining compound 3 (1.4507 g, 1.96 mmol), compound 5
(0.9871 g, 1.80 mmol), compound 6 (0.1478 g, 0.20 mmol),
dichlorobis(triphenylphosphine)palladium (1.40 mg) and toluene (50
ml) under an inert atmosphere, the mixture was heated to
105.degree. C.
[0255] A 20 wt % tetraethylammonium hydroxide aqueous solution (7
ml) was added dropwise to the reaction mixture, which was then
circulated for 2 hours and 20 minutes. After the reaction,
phenylboric acid (26 mg) and
dichlorobis(triphenylphosphine)palladium (1.20 mg) were added and
circulation was continued for 17 hours. Next, a sodium
diethyldithocarbaminate aqueous solution was added and the mixture
was stirred at 80.degree. C. for 2 hours. After cooling, washing
was performed twice with water (26 ml), twice with a 3 wt % acetic
acid aqueous solution (26 ml) and twice with water (26 ml), and the
obtained solution was added dropwise to methanol (311 mL) and
filtered to obtain a precipitate.
[0256] The precipitate was dissolved in toluene (63 mL) and passed
through an alumina column and a silica gel column in that order for
purification. The obtained solution was added dropwise to methanol
(311 ml) and stirred, and then the resulting precipitate was
filtered and dried to obtain 1.49 g of polymer compound 2. The
polystyrene equivalent number-average molecular weight of polymer
compound 2 was 1.1.times.10.sup.5, and the polystyrene equivalent
weight-average molecular weight was 2.9.times.10.sup.5.
[0257] Polymer compound 2 is a random copolymer comprising a
constitutional unit represented by the following formula (2a):
##STR00082##
a constitutional unit represented by the following formula
(2b):
##STR00083##
and a constitutional unit represented by the following formula
(2c):
##STR00084##
in a molar ratio of 50:45:5, as the theoretical value calculated
from the charged starting materials.
Synthesis Example 4
Synthesis of Polymer Compound 3
[0258] After combining compound 7 (1.983 g, 3.98 mmol) represented
by the following formula:
##STR00085##
compound 8 (1.561 g, 3.40 mmol) represented by the following
formula:
##STR00086##
compound 9 (0.258 g, 0.60 mmol) represented by the following
formula:
##STR00087##
dichlorobis(triphenylphosphine)palladium (2.8 mg) and toluene (44
ml) under an inert atmosphere, the mixture was heated to
105.degree. C. A 20 wt % tetraethylammonium hydroxide aqueous
solution (13.3 ml) was added dropwise to the reaction mixture,
which was then circulated for 12 hours.
[0259] After the reaction, phenylboric acid (49 mg),
dichlorobis(triphenylphosphine)palladium (2.8 mg) and toluene (44
mL) were added and circulation was continued for 17 hours. Next, a
sodium diethyldithocarbaminate aqueous solution was added and the
mixture was stirred at 80.degree. C. for 2 hours. After cooling,
washing was performed twice with water (52 ml), twice with a 3 wt %
acetic acid aqueous solution (52 ml) and twice with water (52 ml),
and the obtained solution was added dropwise to methanol (620 mL)
and filtered to obtain a precipitate.
[0260] The precipitate was dissolved in toluene (124 mL) and passed
through an alumina column and a silica gel column in that order for
purification. The obtained solution was added dropwise to methanol
(620 ml) and stirred, and then the resulting precipitate was
filtered and dried to obtain 1.94 g of polymer compound 3. The
polystyrene equivalent number-average molecular weight of polymer
compound 3 was 4.4.times.10.sup.4, and the polystyrene equivalent
weight-average molecular weight was 1.1.times.10.sup.5.
[0261] Polymer compound 3 is a random copolymer comprising a
constitutional unit represented by the following formula (3a):
##STR00088##
a constitutional unit represented by the following formula
(3b):
##STR00089##
and a constitutional unit represented by the following formula
(3c):
##STR00090##
in a molar ratio of 49.9:42.6:7.5, as the theoretical value
calculated from the charged starting materials.
Comparative Example 2
Fabrication and Evaluation of Light Emitting Device 1
[0262] Formation of Hole Injection Layer
A composition for formation of a hole injection layer was coated
onto a glass panel on which an ITO anode had been formed, obtaining
a coating film with a film thickness of 60 nm by spin coating. The
coating film-formed substrate was heated at 200.degree. C. for 10
minutes, and after insolubilizing the coating film, it was allowed
to naturally cool to room temperature to obtain a hole injection
layer. The composition used for formation of the hole injection
layer was a PEDOT:PSS aqueous solution
(poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid, product
name: Baytron), available from Starck-V Tech.
[0263] Formation of Hole Transport Layer
Polymer compound 3 and xylene were combined to a polymer compound 3
concentration of 0.7 wt %, to obtain a composition for formation of
a hole transport layer. The hole injection layer was coated with
the composition for formation of a hole transport layer by spin
coating, to obtain a coating film with a film thickness of 20 nm.
The coating film-formed substrate was heated at 180.degree. C. for
60 minutes, and after insolubilizing the coating film, it was
allowed to naturally cool to room temperature to obtain a hole
transport layer.
[0264] Formation of Luminescent Layer
Polymer compound 1 and xylene were combined to a polymer compound 1
concentration of 1.3 wt %, to obtain a composition for formation of
a luminescent layer. The hole transport layer of the obtained
substrate, which comprised an anode, hole injection layer and hole
transport layer, was coated with the composition for formation of a
luminescent layer by spin coating to obtain a coating film with a
film thickness of 60 nm. The coating film-formed substrate was
heated at 130.degree. C. for 20 minutes, and after evaporating off
the solvent, it was allowed to naturally cool to room temperature
to obtain a luminescent layer.
[0265] Formation of Cathode
The luminescent layer of the obtained substrate, which comprised an
anode, hole injection layer, hole transport layer and luminescent
layer, was subjected to vacuum vapor deposition to continuously
form a barium layer with a film thickness of 5 nm and then an
aluminum layer with a film thickness of 80 nm, thereby forming a
cathode.
[0266] Sealing
The substrate having these laminated layers was removed from the
vacuum vapor deposition apparatus and was sealed with sealing glass
and a two-pack mixture epoxy resin under a nitrogen atmosphere, to
obtain light emitting device 1.
[0267] Evaluation
Blue electroluminescence (EL) was observed when a voltage was
applied to the light emitting device 1. The maximum current
efficiency of the light emitting device 1 was 7.3 cd/A, and the
maximum external quantum yield was 6.8%. Also, the luminance
lifetime, which is the time from initial luminance of 3400
cd/m.sup.2 to luminance half-life was 1.7 hours.
Example 2
Fabrication and Evaluation of Light Emitting Device 2
[0268] Fabrication of Light Emitting Device 2
Light emitting device 2 was fabricated in the same manner as
Comparative Example 2, except that polymer compound 2 was used
instead of polymer compound 1 in Comparative Example 2.
[0269] Evaluation
Blue electroluminescence (EL) was observed when a voltage was
applied to the light emitting device 2. The maximum current
efficiency of the light emitting device 2 was 9.1 cd/A, and the
maximum external quantum yield was 7.8%. A voltage was applied for
the same number of emitted photons as Comparative Example 2, and
the luminance lifetime, as the time from initial luminance of 5800
cd/m.sup.2 to luminance half-life was 2.6 hours.
Synthesis Example 5
Synthesis of Polymer Compound 4
[0270] After combining compound 4 (3.863 g, 7.283 mmol), compound 8
(3.177 g, 6.919 mmol), compound 9 (0.1563 g, 0.364 mmol),
trioctylmethylammonium chloride (trade name: Aliquat 336 (product
of Aldrich Co.), 3.1 ml), dichlorobis(triphenylphosphine)palladium
(4.9 mg) and toluene (50 ml) under an inert atmosphere, the mixture
was heated to 105.degree. C.
[0271] A 2.0 M Na.sub.2CO.sub.3 aqueous solution (14 ml) was added
dropwise to the reaction mixture, which was then circulated for
16.5 hours. After the reaction, phenylboric acid (0.5 g) was added
and circulation was continued for 7 hours. The organic layer
obtained by removing the aqueous layer was added with 50 ml of
water, stirred, allowed to stand still, and the aqueous layer that
became separated was removed. The obtained organic layer was added
with a sodium N,N-diethyldithiocarbamate aqueous solution (0.75 g)
and water (50 ml), and stirred at 85.degree. C. for 16 hours. The
obtained reaction mixture was allowed to stand still, the aqueous
layer that became separated was removed, the remaining organic
layer was washed three times with 100 ml of water, and the obtained
solvent was allowed to pass through a silica gel column and a basic
alumina column. The obtained solution was added dropwise to
methanol and stirred, and then the resulting precipitate was
filtered and dried to obtain 4.2 g of polymer compound 4. The
polystyrene equivalent number-average molecular weight of polymer
compound 4 was 4.4.times.10.sup.4, and the polystyrene equivalent
weight-average molecular weight was 1.2.times.10.sup.5.
[0272] Polymer compound 4 is a random copolymer comprising a
constitutional unit represented by the following formula (4a):
##STR00091##
a constitutional unit represented by the following formula
(4b):
##STR00092##
and a constitutional unit represented by the following formula
(4c):
##STR00093##
in a molar ratio of 50.0:42.5:7.5, as the theoretical value
calculated from the charged starting materials.
Comparative Example 3
Fabrication and Evaluation of Light Emitting Device 3)
[0273] Fabrication of Light Emitting Device 3
Light emitting device 3 was fabricated in the same manner as
Comparative Example 2, except that polymer compound 4 was used
instead of polymer compound 3 in Comparative Example 2.
[0274] Evaluation
Blue electroluminescence (EL) was observed when a voltage was
applied to the light emitting device 3. The maximum current
efficiency of the light emitting device 3 was 7.4 cd/A, and the
maximum external quantum yield was 5.2%. Also, the luminance
lifetime, which is the time from initial luminance of 4500
cd/m.sup.2 to luminance half-life was measured to be 6.6 hours.
Example 3
Fabrication and Evaluation of Light Emitting device 4
[0275] Fabrication of Light Emitting Device 4
Light emitting device 4 was fabricated in the same manner as
Comparative Example 2, except that polymer compound 2 was used
instead of polymer compound 1 and polymer compound 4 was used
instead of polymer compound 3 in Comparative Example 2.
[0276] Evaluation
Blue electroluminescence (EL) was observed when a voltage was
applied to the light emitting device 4. The maximum current
efficiency of the light emitting device 4 was 8.5 cd/A, and the
maximum external quantum yield was 5.8%. A voltage was applied for
the same number of emitted photons as Comparative Example 3, and
the luminance lifetime, as the time from initial luminance of 4600
cd/m.sup.2 to luminance half-life was 26.8 hours.
Example 4
Synthesis of Polymer Compound 5
[0277] After combining compound 3 (2.1805 g, 2.95 mmol), compound 5
(1.4808 g, 2.70 mmol), compound 10 (0.1420 g, 0.30 mmol)
represented by the following formula:
##STR00094##
dichlorobis(triphenylphosphine)palladium (2.1 mg) and toluene (70
ml) under an inert atmosphere, the mixture was heated to
105.degree. C.
[0278] A 20 wt % tetraethylammonium hydroxide aqueous solution (10
ml) was added dropwise to the reaction mixture, which was then
circulated for 2 hours. After the reaction, phenylboric acid (37
mg) and dichlorobis(triphenylphosphine)palladium (2.1 mg) were
added and circulation was continued for 17 hours. Next, a sodium
N,N-diethyldithiocarbamate aqueous solution was added and the
mixture was stirred at 80.degree. C. for 2 hours. After cooling,
washing was performed twice with water (39 ml), twice with a 3 wt %
acetic acid aqueous solution (39 ml) and twice with water (39 ml),
and the obtained solution was added dropwise to methanol (500 mL)
and filtered to obtain a precipitate. The precipitate was dissolved
in toluene (94 mL) and passed through an alumina column and a
silica gel column in that order for purification. The obtained
solution was added dropwise to methanol (325 ml) and stirred, and
then the resulting precipitate was filtered and dried to obtain
1.77 g of polymer compound 5. The polystyrene equivalent
number-average molecular weight of polymer compound 5 was
1.3.times.10.sup.5, and the polystyrene equivalent weight-average
molecular weight was 3.4.times.10.sup.5.
[0279] Polymer compound 5 is a random copolymer comprising a
constitutional unit represented by the following formula (5a):
##STR00095##
a constitutional unit represented by the following formula
(5b):
##STR00096##
and a constitutional unit represented by the following formula
(5c):
##STR00097##
in a molar ratio of 50:45:5, as the theoretical value calculated
from the charged starting materials.
Example 5
Fabrication and Evaluation of Light Emitting Device 5
[0280] Fabrication of Light Emitting Device 5
Light emitting device 5 was fabricated in the same manner as
Comparative Example 2, except that polymer compound 5 was used
instead of polymer compound 1 and polymer compound 4 was used
instead of polymer compound 3 in Comparative Example 2.
[0281] Evaluation
[0282] Blue electroluminescence (EL) was observed when a voltage
was applied to the light emitting device 5. The maximum current
efficiency of the light emitting device 5 was 10.8 cd/A, and the
maximum external quantum yield was 6.7%. Also, the luminance
lifetime, which is the time from initial luminance of 6040
cd/m.sup.2 to luminance half-life was measured to be 37.6
hours.
Example 6
Synthesis of Polymer Compound 6
[0283] After combining compound 11 (4.3884 g, 5.94 mmol)
represented by the following formula:
##STR00098##
compound 5 (2.9621 g, 5.40 mmol), compound 6 (0.4430 g, 0.60 mmol),
palladium (II) acetate (3.24 mg), tris(o-methoxyphenyl)phosphine
(19.3 mg) and toluene (67 ml) under an inert atmosphere, the
mixture was heated to 105.degree. C.
[0284] A 20 wt % tetraethylammonium hydroxide aqueous solution (20
ml) was added dropwise to the reaction mixture, which was then
circulated for 2 hours. After the reaction, phenylboric acid (370
mg) was added and circulation was continued for 2 hours. Next, a
sodium diethyldithocarbaminate aqueous solution was added and the
mixture was stirred at 65.degree. C. for 2 hours. After cooling,
washing was performed twice with water (39 ml), twice with a 3 wt %
acetic acid aqueous solution (39 ml) and twice with water (39 ml),
and the obtained solution was added dropwise to methanol (500 ml)
and filtered to obtain a precipitate.
[0285] The precipitate was dissolved in toluene (94 ml) and passed
through an alumina column and a silica gel column in that order for
purification. The obtained solution was added dropwise to methanol
(325 ml) and stirred, and then the resulting precipitate was
filtered and dried to obtain 3.49 g of polymer compound 6. The
polystyrene equivalent number-average molecular weight of polymer
compound 6 was 1.5.times.10.sup.5, and the polystyrene equivalent
weight-average molecular weight was 3.8.times.10.sup.5.
[0286] Polymer compound 6 is a random copolymer comprising a
constitutional unit represented by the following formula (6a):
##STR00099##
a constitutional unit represented by the following formula
(6b):
##STR00100##
and a constitutional unit represented by the following formula
(6c):
##STR00101##
in a molar ratio of 50:45:5, as the theoretical value calculated
from the charged starting materials.
Comparative Example 4
Fabrication and Evaluation of Light Emitting Device 6
[0287] Fabrication of Light Emitting Device 6
Light emitting device 6 was fabricated in the same manner as
Comparative Example 2, except that hole transport layer was formed
with a film thickness of 50 nm instead of 60 nm and polymer
compound 4 was used instead of polymer compound 3 in Comparative
Example 2.
[0288] Evaluation
[0289] Blue electroluminescence (EL) was observed when a voltage
was applied to the light emitting device 6. The maximum current
efficiency of the light emitting device 6 was 6.5 cd/A, and the
maximum external quantum yield was 4.6%. Also, the luminance
lifetime, which is the time from initial luminance of 4030
cd/m.sup.2 to luminance half-life was measured to be 8.8 hours.
Example 7
Fabrication and Evaluation of Light Emitting Device 7
[0290] Fabrication of Light Emitting Device 7
Light emitting device 7 was fabricated in the same manner as
Comparative Example 2, except that hole transport layer was formed
with a film thickness of 50 nm instead of 60 nm, polymer compound 6
was used instead of polymer compound 1 and polymer compound 4 was
used instead of polymer compound 3 in Comparative Example 2.
[0291] Evaluation
Blue electroluminescence (EL) was observed when a voltage was
applied to the light emitting device 7. The maximum current
efficiency of the light emitting device 7 was 7.6 cd/A, and the
maximum external quantum yield was 5.5%. A voltage was applied for
the same number of emitted photons as Comparative Example 4, and
the luminance lifetime, as the time from initial luminance of 3955
cd/m.sup.2 to luminance half-life was 25.4 hours.
Comparative Example 5
Synthesis of Polymer Compound 7
[0292] After combining compound 12 (1.9065 g, 2.97 mmol)
represented by the following formula:
##STR00102##
compound 5 (1.4808 g, 2.70 mmol), compound 10 (0.1420 g, 0.30
mmol), dichlorobis(triphenylphosphine)palladium (2.11 mg) and
toluene (71 ml) under an inert atmosphere, the mixture was heated
to 105.degree. C.
[0293] A 20 wt % tetraethylammonium hydroxide aqueous solution (10
ml) was added dropwise to the reaction mixture, which was then
circulated for 3 hours. After the reaction, phenylboric acid (37
mg) and dichlorobis(triphenylphosphine)palladium (2.11 mg) were
added and circulation was continued for 17 hours. Next, a sodium
diethyldithocarbaminate aqueous solution was added and the mixture
was stirred at 80.degree. C. for 2 hours. After cooling, washing
was performed twice with water (39 ml), twice with a 3 wt % acetic
acid aqueous solution (39 ml) and twice with water (39 ml), and the
obtained solution was added dropwise to methanol (500 ml) and
filtered to obtain a precipitate. The precipitate was dissolved in
toluene (94 ml) and passed through an alumina column and a silica
gel column in that order for purification. The obtained solution
was added dropwise to methanol (325 ml) and stirred, and then the
resulting precipitate was filtered and dried to obtain 1.77 g of
polymer compound 7. The polystyrene equivalent number-average
molecular weight of polymer compound 7 was 1.1.times.10.sup.5, and
the polystyrene equivalent weight-average molecular weight was
3.5.times.10.sup.5.
[0294] Polymer compound 7 is a random copolymer comprising a
constitutional unit represented by the following formula (7a):
##STR00103##
and a constitutional unit represented by the following formula
(7b):
##STR00104##
in a molar ratio of 95:5, as the theoretical value calculated from
the charged starting materials.
Synthesis Example 6
Synthesis of Compound 13
[0295] Under the nitrogen atmosphere, 3,5-dibromotoluene (40.79 g,
159.94 mmol) and tetrahydrofuran (200 ml) were added to a 4-necked
flask and dissolved. Next, a 1.6 M n-butyllithium/n-hexane solution
(100 ml, 159.94 mmol) was slowly added dropwise at -78.degree. C.
and stirred at the same temperature for 1 hour. Next,
tetrahydrofuran (500 ml) was added at -60.degree. C. and the
mixture was obtained. Under the nitrogen atmosphere, this mixture
was added to a 2 L 4-necked flask containing iodine (81.19 g,
319.88 mmol) and stirred at -70.degree. C. or less.
[0296] Subsequently, after stirring for one hour at 0.degree. C.,
an aqueous solution of 10% Na.sub.2S.sub.2O.sub.3 (300 ml) was
added and stirred. This reaction mixture was extracted with
n-hexane (300 ml.times.2), the obtained organic layer was washed
with saturated saline and added with sodium sulfate anhydrous and
stirred. The obtained filtrate was subjected to vacuum
concentration. Then, by distillation under reduced pressure, the
desired chemical compound 13 (33 g, 69% yield constant) was
obtained.
##STR00105##
Synthesis Example 7
Synthesis of Compound 15
[0297] Under the Argon atmosphere, a compound 14 (37.75 g, 183.17
mmol) represented by the following formula:
##STR00106##
compound 13 (53.45 g, 180.00 mmol), tetrahydrofuran (1800 ml),
palladium [tetrakis(triphenylphosphine)] (10.58 g, 9.16 mmol) and
Ag.sub.2CO.sub.3 (101.02 g, 366.34 mmol) was added and stirred for
14 hours at room temperature. Next, the reaction mixture was
purified by silica gel column chromatography (developing solvent:
hexan) and thus 40.02 g of the desired compound 15 was
obtained.
##STR00107##
Synthesis Example 8
Synthesis of Compound 17
[0298] Under the nitrogen atmosphere, a compound 15 (27.7 g, 83.57
mmol) and tetrahydrofuran (250 ml) was added to a 3-necked flask,
dissolved, and cooled to -78.degree. C. Then, 1.6 M
n-butyllithium/n-hexane solution (52.2 ml) was added dropwise at
-65.degree. C., and stirred for an hour at the same temperature.
Next, a solvent consisting of a compound 16 (14.72 g, 39.78 mmol)
is represented by the following formula:
##STR00108##
and tetrahydrofuran (45 ml) was added at -60.degree. C. or less and
stirred for 2.5 hours at the same temperature. Next, after stirring
for 1 hour at room temperature, the saturated ammonium chloride
aqueous solvent is added dropwise and stirred. This reaction
mixture was extracted by n-hexane (300 ml.times.2). The obtained
organic layer was washed with saturated saline (300 ml), added with
the sodium sulfate anhydrous, stirred, and filtered. The obtained
filterate is subjected to vacuum concentration, the solvent is
distilled away, and thus the concentrate A was obtained. Next,
under the nitrogen atmosphere, boron trifluoride--ethyl ether
complex (BF.sub.3.OEt.sub.2, 28.2 g, 198.90 mmol) is added to a
3-necked flask, cooled to 0.degree. C., and a solvent consisting of
the above concentrate A and dichloromethane (80 ml) is slowly added
and stirred for 2.5 hours at room temperature. Next, it is added
with water (100 ml) and stirred at 0.degree. C. This reaction
mixture was extracted with chloroform (150 ml.times.2) at room
temperature. The obtained organic layer was washed with saturated
sodium bicarbonate (100 ml.times.2) and saturated saline (100 ml),
further added with Sodium sulfate anhydrous, stirred and the
filtrate obtained by filtering was subjected to vacuum
concentration. Afterwards, it is recrystallized with ethyl acetate
and methanol, and 12.5 g of the desired compound 17 was
obtained.
##STR00109##
Synthesis Example 9
Synthesis of Compound 19
[0299] Under the nitrogen atmosphere, a compound 17 (7.30 g, 8.86
mmol), compound 18 (5.40 g, 21.25 mmol) represented by the
following formula:
##STR00110##
[1,1'-Bis(diphenylphosphino)ferrocene]dichloropalladium(II)--dichlorometh-
ane complex (PdCl.sub.2(dppf)CH.sub.2Cl.sub.2, 0.43 g, 0.53 mmol),
1,1'-Bis(diphenylphosphino)ferrocene (0.30 g, 0.53 mmol), potassium
acetate (5.27 g, 53.13 mmol) and 1,4-dioxane (61 ml) were added to
4-necked flask and stirred at 105.degree. C. for 8 hours.
[0300] Then, the reaction mixture was passed through the filter
that is carpeted with celite at room temperature, washed with
toluene, and the obtained filtrate is subjected to vacuum
concentration to distill away the solvent. The obtained concentrate
is added with hexan (300 ml) and activated carbon (16 g), stirred
at 70.degree. C. for an hour, passed through the filter that is
carpeted with celite, and the solvent is removed by subjecting the
obtained filtrate to vacuum concentration. Then, recrystallization
with methanol was performed. By further recrystallizing with hexan,
3.18 g of the desired compound 19 was obtained.
##STR00111##
Example 8
Synthesis of Polymer Compound 8
[0301] After combining compound 19 (2.7289 g, 2.97 mmol). compound
5 (1.4807 g, 2.70 mmol), compound 10 (0.1421 g, 0.30 mmol),
dichlorobis(triphenylphosphine)palladium (2.18 mg) and toluene (71
ml) under an inert atmosphere, the mixture was heated to
105.degree. C.
[0302] A 20 wt % tetraethylammonium hydroxide aqueous solution (10
ml) was added dropwise to the reaction mixture, which was then
circulated for 1 hours. After the reaction, phenylboric acid (37
mg) and dichlorobis(triphenylphosphine)palladium (2.1 mg) were
added and circulation was continued for 19.5 hours. Next, a sodium
diethyldithocarbaminate aqueous solution was added and the mixture
was stirred at 80.degree. C. for 2 hours. After cooling, washing
was performed twice with water (39 ml), twice with a 3 wt % acetic
acid aqueous solution (39 ml) and twice with water (39 ml), and the
obtained solution was added dropwise to methanol (500 ml) and
filtered to obtain a precipitate.
[0303] The precipitate was dissolved in toluene (94 ml) and passed
through an alumina column and a silica gel column in that order for
purification. The obtained solution was added dropwise to methanol
(325 ml) and stirred, and then the resulting precipitate was
filtered and dried to obtain 2.61 g of polymer compound 8. The
polystyrene equivalent number-average molecular weight of polymer
compound 8 was 2.3.times.10.sup.5, and the polystyrene equivalent
weight-average molecular weight was 7.0.times.10.sup.5.
[0304] Polymer compound 8 is a random copolymer comprising a
constitutional unit represented by the following formula (8a):
##STR00112##
a constitutional unit represented by the following formula
(8b):
##STR00113##
and a constitutional unit represented by the following formula
(8c):
##STR00114##
in a molar ratio of 50:45:5, as the theoretical value calculated
from the charged starting materials.
Comparative Example 6
Fabrication and Evaluation of Light Emitting Device 8
[0305] Fabrication of Light Emitting Device 8
Light emitting device 8 was fabricated in the same manner as
Comparative Example 2, except that hole transport layer was formed
with a film thickness of 50 nm instead of 60 nm, polymer compound 7
was used instead of polymer compound 1 and polymer compound 4 was
used instead of polymer compound 3 in Comparative Example 2.
[0306] Evaluation
Blue electroluminescence (EL) was observed when a voltage was
applied to the light emitting device 8. The maximum current
efficiency of the light emitting device 8 was 6.4 cd/A, and the
maximum external quantum yield was 4.8%. Also, the luminance
lifetime, which is the time from initial luminance of 3800
cd/m.sup.2 to luminance half-life was measured to be 9.3 hours.
Example 9
Fabrication and Evaluation of Light Emitting Device 9
[0307] Fabrication of Light Emitting Device 9
Light emitting device 9 was fabricated in the same manner as
Comparative Example 2, except that hole transport layer was formed
with a film thickness of 50 nm instead of 60 nm, polymer compound 8
was used instead of polymer compound 1 and polymer compound 4 was
used instead of polymer compound 3 in Comparative Example 2.
[0308] Evaluation
[0309] Blue electroluminescence (EL) was observed when a voltage
was applied to the light emitting device 9. The maximum current
efficiency of the light emitting device 9 was 13.3 cd/A, and the
maximum external quantum yield was 7.8%. A voltage was applied for
the same number of emitted photons as Comparative Example 6, and
the luminance lifetime, as the time from initial luminance of 4900
cd/m.sup.2 to luminance half-life was 81.8 hours.
Example 10
Fabrication and Evaluation of Light Emitting Device 10
[0310] Fabrication of Light Emitting Device 10
Light emitting device 10 was fabricated in the same manner as
Comparative Example 2, except that hole transport layer was formed
with a film thickness of 50 nm instead of 60 nm, polymer compound 5
was used instead of polymer compound 1 and polymer compound 4 was
used instead of polymer compound 3 in Comparative Example 2.
[0311] Evaluation
Blue electroluminescence (EL) was observed when a voltage was
applied to the light emitting device 10. The maximum current
efficiency of the light emitting device 10 was 10.8 cd/A, and the
maximum external quantum yield was 6.6%. A voltage was applied for
the same number of emitted photons as Comparative Example 6, and
the luminance lifetime, as the time from initial luminance of 4715
cd/m.sup.2 to luminance half-life was 69.5 hours.
REFERENCE SIGNS LIST
[0312] 10, 20 . . . substrate, 11, 21 . . . anode, 12, 22 . . .
charge injection layer, 13 . . . hole transport layer, 14, 23 . . .
luminescent layer, 15 . . . electron transport layer, 16 . . .
charge injection layer, 17, 24 . . . cathode, 25 . . . protective
layer, 100, 110 . . . light emitting device, 200 . . . planar light
source.
* * * * *